openchamber/packages/web/server/lib/opencode/DOCUMENTATION.md

# OpenCode Module Documentation

## Purpose
This module provides OpenCode server integration utilities for the web server runtime, including configuration management and provider authentication.

## Entrypoints and structure
- `packages/web/server/lib/opencode/index.js`: public entrypoint (currently baseline placeholder).
- `packages/web/server/lib/opencode/auth.js`: provider authentication file operations.
- `packages/web/server/lib/opencode/auth-state-runtime.js`: managed OpenCode server auth password/header runtime.
- `packages/web/server/lib/opencode/cli-options.js`: CLI/environment option parsing for server startup arguments.
- `packages/web/server/lib/opencode/cli-entry-runtime.js`: CLI entrypoint runtime that detects direct execution, parses CLI options, and starts server bootstrap.
- `packages/web/server/lib/opencode/routes.js`: OpenCode/provider settings and auth-related route registration.
- `packages/web/server/lib/opencode/lifecycle.js`: OpenCode process lifecycle runtime (startup, restart, readiness, health monitoring). After readiness it warms the most recently used directories (`getWarmupDirectories` dep, sequential and best-effort) because OpenCode initializes each directory lazily on first request and that cost would otherwise be paid by the user's first interactive session open.
- `packages/web/server/lib/opencode/env-runtime.js`: OpenCode CLI/binary resolution and shell environment runtime.
- `packages/web/server/lib/opencode/env-config.js`: OpenCode-related environment variable parsing and validation (host/port/hostname).
- `packages/web/server/lib/opencode/hmr-state-runtime.js`: HMR-persistent runtime state initialization, auth-state bootstrap, and HMR sync helpers.
- `packages/web/server/lib/opencode/bootstrap-runtime.js`: base app bootstrap runtime for status/auth/tts/notification/OpenChamber route wiring.
- `packages/web/server/lib/opencode/network-runtime.js`: OpenCode URL construction, health-probe readiness checks, and API prefix runtime.
- `packages/web/server/lib/opencode/project-directory-runtime.js`: request-scoped and settings-backed project directory resolution/validation runtime.
- `packages/web/server/lib/opencode/config-entity-routes.js`: route registration for agent/command/MCP config orchestration and reload semantics.
- `packages/web/server/lib/opencode/snippets.js`: opencode-snippets-compatible snippet file CRUD, discovery, and hashtag expansion.
- `packages/web/server/lib/opencode/cli-options.js`: CLI/environment option parsing for server startup arguments.
- `packages/web/server/lib/opencode/core-routes.js`: server status/system routes, auth/access guard routes, and settings utility route registration.
- `packages/web/server/lib/opencode/shutdown-runtime.js`: graceful shutdown orchestration runtime for watcher/session/terminal/process/server teardown.
- `packages/web/server/lib/opencode/server-startup-runtime.js`: server listen/startup tunnel flow and process/signal handler orchestration runtime.
- `packages/web/server/lib/opencode/static-routes-runtime.js`: static asset/SPA fallback route registration and manifest route wiring.
- `packages/web/server/lib/opencode/feature-routes-runtime.js`: feature route composition runtime for dynamic import-backed config/skill/provider route registration.
- `packages/web/server/lib/opencode/opencode-resolution-runtime.js`: OpenCode binary resolution snapshot runtime for settings routes and diagnostics.
- `packages/web/server/lib/opencode/upgrade-capability.js`: authoritative upgrade ownership policy for the active OpenCode runtime. Bundled, external, and unresolved runtimes fail closed; only managed non-bundled runtimes delegate upgrades to OpenCode.
- `packages/web/server/lib/opencode/tunnel-wiring-runtime.js`: tunnel service/routes composition runtime and active-port wiring for main server startup.
- `packages/web/server/lib/opencode/startup-pipeline-runtime.js`: server startup tail orchestration runtime for terminal/proxy/static/start-listen flow.
- `packages/web/server/lib/opencode/startup-performance.js`: opt-in startup phase diagnostics with fixed labels and numeric metadata allowlists.
- `packages/web/server/lib/agent-tool/runtime.js`: managed OpenCode custom-tool materialization, environment injection, loopback authentication, and fixed CLI action dispatch.
- `packages/web/server/lib/system-prompt/runtime.js`: opt-in managed OpenCode system-prompt optimizer materialization and plugin injection.
- `packages/web/server/lib/opencode/server-utils-runtime.js`: shared server runtime utilities for OpenCode proxy wiring, OpenCode port/readiness helpers, and snapshot fetchers.
- `packages/web/server/lib/opencode/openchamber-routes.js`: OpenChamber update and models metadata route registration.
- `packages/web/server/lib/opencode/pwa-manifest-routes.js`: PWA manifest route registration with recent-session shortcut resolution and short-lived caching.
- `packages/web/server/lib/opencode/project-icon-routes.js`: project icon upload/read/discovery route registration and icon storage orchestration.
- `packages/web/server/lib/opencode/skill-routes.js`: route registration for skill config CRUD, supporting files, and skills catalog scan/install flows.
- `packages/web/server/lib/opencode/settings-runtime.js`: Settings persistence runtime (disk IO, migrations, normalization, project validation, and persisted update serialization).
- `packages/web/server/lib/opencode/settings-helpers.js`: Settings payload sanitization/format helpers runtime for response shaping and persisted merge prep.
- `packages/web/server/lib/opencode/settings-normalization-runtime.js`: path/settings/tunnel normalization and sanitization helpers runtime used by settings/routes/config wiring.
- `packages/web/server/lib/opencode/theme-runtime.js`: custom theme JSON validation and theme directory loading runtime for settings utility routes.
- `packages/web/server/lib/opencode/proxy.js`: OpenCode API/SSE forwarding and readiness-gate route registration.
- `packages/web/server/lib/opencode/session-runtime.js`: session status/attention/activity runtime for OpenCode SSE events.
- `packages/web/server/lib/opencode/watcher.js`: global SSE watcher runtime for push/session event fanout.
- `packages/web/server/lib/opencode/shared.js`: shared utilities for config, markdown, skills, and git helpers.
- `packages/web/server/lib/ui-auth/ui-auth.js`: UI session authentication runtime (outside OpenCode module).
- `packages/web/server/lib/ui-auth/ui-passkeys.js`: UI passkey storage and WebAuthn registration/authentication helpers (outside OpenCode module).

## Public exports (auth.js)
- `readAuthFile()`: Reads and parses `~/.local/share/opencode/auth.json`.
- `writeAuthFile(auth)`: Writes auth file with automatic backup.
- `removeProviderAuth(providerId)`: Removes a provider's auth entry.
- `getProviderAuth(providerId)`: Returns auth for a specific provider or null.
- `listProviderAuths()`: Returns list of provider IDs with configured auth.
- `AUTH_FILE`: Auth file path constant.
- `OPENCODE_DATA_DIR`: OpenCode data directory path constant.

## Public exports (providers.js)
- `getProviderSources(providerId, workingDirectory)`: Resolves which OpenCode config layers define a provider.
- `upsertProviderConfig(providerId, config, workingDirectory, scope?, options?)`: Validates and writes a custom OpenAI-compatible provider block (`npm`, `name`, `options.baseURL`, `models`, optional `env`/`headers`) into the user/project/custom config layer. Does not store API keys. Requires `config.env` or `options.hasStoredAuth` (auth already written via OpenCode `auth.set`). Edit flows must pass the provider's effective existing layer (`custom` > `project` > `user`) so updates do not create a global user override.
- `validateCustomProviderConfig(providerId, config, options?)`: Structural validation for custom provider payloads (id format, http(s) base URL, models, credentials via `env` or `hasStoredAuth`).
- `removeProviderConfig(providerId, workingDirectory, scope?)`: Removes a provider block from the selected config layer.

## Public exports (shared.js)
- `OPENCODE_CONFIG_DIR`, `AGENT_DIR`, `COMMAND_DIR`, `SKILL_DIR`, `CONFIG_FILE`: Path constants. `OPENCODE_CONFIG` is resolved at call time for the custom config layer path.
- `AGENT_SCOPE`, `COMMAND_SCOPE`, `SKILL_SCOPE`: Scope constants with USER and PROJECT values.
- `ensureDirs()`: Creates required OpenCode directories.
- `parseMdFile(filePath)`, `writeMdFile(filePath, frontmatter, body)`: Markdown file operations with YAML frontmatter.
- `getConfigPaths(workingDirectory)`, `readConfigLayers(workingDirectory)`, `readConfig(workingDirectory)`: Config file operations with layer merging (user, project, custom).
- `writeConfig(config, filePath)`: Writes config with automatic backup.
- `getJsonEntrySource(layers, sectionKey, entryName)`: Resolves which config layer provides an entry.
- `getJsonWriteTarget(layers, preferredScope)`: Determines write target for config updates.
- `getAncestors(startDir, stopDir)`, `findWorktreeRoot(startDir)`: Git worktree helpers.
- `isPromptFileReference(value)`, `resolvePromptFilePath(reference)`, `writePromptFile(filePath, content)`: Prompt file reference handling.
- `walkSkillMdFiles(rootDir)`: Recursively finds all SKILL.md files.
- `addSkillFromMdFile(skillsMap, skillMdPath, scope, source)`: Parses and indexes a skill file.
- `resolveSkillSearchDirectories(workingDirectory)`: Returns skill search path order (config, project, home, custom).
- `listSkillSupportingFiles(skillDir)`, `readSkillSupportingFile(skillDir, relativePath)`, `writeSkillSupportingFile(skillDir, relativePath, content)`, `deleteSkillSupportingFile(skillDir, relativePath)`: Skill supporting file management.

## Public exports (routes.js)
- `registerOpenCodeRoutes(app, dependencies)`: Registers OpenCode-owned HTTP routes and internal module runtime:
  - `GET /api/config/settings`
  - `PUT /api/config/settings`
  - `GET /api/config/opencode-resolution`
  - `POST /api/opencode/upgrade` (enforces the active runtime's upgrade capability, serializes supported OpenCode upgrades, then restarts managed OpenCode so the new binary is active)
  - `GET /api/opencode/upgrade-status` (returns version availability plus the authoritative `upgrade.supported`, `upgrade.manager`, and `upgrade.reason` capability)
  - `POST /api/opencode/directory`
  - `GET /api/provider/:providerId/source`
  - `PUT /api/provider` (create/update custom OpenAI-compatible provider config in OpenCode user/project/custom layers via `scope`; secrets stay in auth via the OpenCode auth API)
  - `DELETE /api/provider/:providerId/auth`
- Owns lazy auth library loading for provider auth checks/removal.
- Keeps route behavior independent from composition root; `index.js` now supplies dependencies only.

## Public exports (session-runtime.js)
- `createSessionRuntime({ writeSseEvent, getNotificationClients, broadcastEvent? })`: creates runtime-owned state machine and APIs for session status.
- Returned API:
  - `processOpenCodeSsePayload(payload)`
  - `getSessionActivitySnapshot()`
  - `getActiveSessionCount()`
  - `getSessionStateSnapshot()`
  - `getSessionAttentionSnapshot()`
  - `getSessionState(sessionId)`
  - `getSessionAttentionState(sessionId)`
  - `markSessionViewed(sessionId, clientId)`
  - `markSessionUnviewed(sessionId, clientId)`
  - `markUserMessageSent(sessionId)`
  - `resetAllSessionActivityToIdle()`
  - `dispose()`

The runtime maintains active-session count incrementally from idempotent activity phase transitions. Upstream stall-timeout and lifecycle health checks read it in O(1); the hourly cleanup removes activity phases older than 24 hours without broadcasting synthetic state transitions. Snapshot generation remains reserved for the session-activity API.

## Public exports (lifecycle.js)
- `createOpenCodeLifecycleRuntime(dependencies)`: creates lifecycle runtime for managed/external OpenCode process orchestration.
- Returned API:
  - `startOpenCode()`
  - `restartOpenCode()`
  - `waitForOpenCodeReady(timeoutMs?, intervalMs?)`
  - `waitForAgentPresence(agentName, timeoutMs?, intervalMs?)`
  - `refreshOpenCodeAfterConfigChange(reason, options?)`
  - `bootstrapOpenCodeAtStartup()`
  - `startHealthMonitoring(healthCheckIntervalMs)`
  - `waitForPortRelease(port, timeoutMs, hostname?)`
  - `killProcessOnPort(port)`

Managed OpenCode launch also merges the environment returned by the agent-tool
runtime. PATH and `OPENCODE_SERVER_PASSWORD` remain lifecycle-owned and cannot
be replaced by injected values. External OpenCode processes receive no
OpenChamber tool injection. Managed launch env strips AppImage `ARGV0` before
spawn so zsh-backed OpenCode tools do not rewrite child argv[0] to the AppImage
path (#2588).

Set `OPENCHAMBER_STARTUP_PERF=1` to emit bounded startup phase records for server listen, managed OpenCode preparation/readiness, and proxy readiness holds. Every OpenCode bootstrap emits one terminal `opencode.bootstrap.ready` or `opencode.bootstrap.error` event, including reused and external server paths. Records contain controlled phase/outcome/route labels and timing values only; they never contain request URLs, runtime keys, directories, session IDs, credentials, or content.

macOS `say` voice enumeration starts concurrently with server composition. The server listener and managed OpenCode startup do not wait for it; `/api/tts/say/status` awaits the same authoritative capability promise when queried before enumeration completes.

Transport-triggered health checks share the periodic monitor's failure accounting interval. Rapid WS reconnect callbacks therefore cannot exhaust the managed-process restart threshold using one cached unhealthy result; an exited managed process still restarts immediately.

## Public exports (env-runtime.js)
- `createOpenCodeEnvRuntime(dependencies)`: creates runtime that owns OpenCode CLI environment and binary discovery state.
- OpenCode CLI resolution order is persisted settings, environment overrides, bundled Desktop CLI when available, PATH, known install locations, then platform shell discovery.
- Returned API:
  - `applyLoginShellEnvSnapshot()`
  - `getLoginShellEnvSnapshot()`
  - `ensureOpencodeCliEnv()`
  - `applyOpencodeBinaryFromSettings()`
  - `resolveOpencodeCliPath()`
  - `resolveManagedOpenCodeLaunchSpec(opencodePath)`: resolves the effective managed OpenCode launch target, unwrapping Windows package-manager shims to a direct native binary or explicit runtime+script when possible.
  - `resolveGitBinaryForSpawn()`
  - `resolveWslExecutablePath()`
  - `buildWslExecArgs(execArgs, distroOverride?)`
  - `isExecutable(filePath)`
  - `searchPathFor(binaryName, searchPath?)`: resolves an executable from the supplied PATH value, defaulting to the process PATH.
  - `clearResolvedOpenCodeBinary()`

## Public exports (env-config.js)
- `resolveOpenCodeEnvConfig(options?)`: resolves and validates OpenCode host/port/hostname environment configuration.
- Returned object fields:
  - `configuredOpenCodePort`
  - `configuredOpenCodeHost`
  - `effectivePort`
  - `configuredOpenCodeHostname`

## Public exports (hmr-state-runtime.js)
- `createHmrStateRuntime(dependencies)`: creates runtime for HMR state container initialization and runtime<->HMR state synchronization.
- Returned API:
  - `getOrCreateHmrState()`
  - `ensureUserProvidedOpenCodePassword(hmrState)`
  - `getUserProvidedOpenCodePassword(hmrState)`
  - `resolveOpenCodeAuthFromState({ hmrState, userProvidedOpenCodePassword })`
  - `syncStateFromRuntime(hmrState, runtime)`
  - `restoreRuntimeFromState({ hmrState, userProvidedOpenCodePassword })`

## Public exports (bootstrap-runtime.js)
- `createBootstrapRuntime(dependencies)`: creates runtime for base app route bootstrap and UI auth controller initialization.
- Returned API:
  - `setupBaseRoutes(app, options)`

## Public exports (network-runtime.js)
- `createOpenCodeNetworkRuntime(dependencies)`: creates runtime for OpenCode network and URL concerns.
- Returned API:
  - `waitForReady(url, timeoutMs?)`
  - `normalizeApiPrefix(prefix)`
  - `setDetectedOpenCodeApiPrefix()`
  - `buildOpenCodeUrl(path, prefixOverride?)`
  - `ensureOpenCodeApiPrefix()`
  - `scheduleOpenCodeApiDetection()`

## Public exports (settings-runtime.js)
- `createSettingsRuntime(dependencies)`: creates settings lifecycle runtime for read/migrate/persist concerns.
- Returned API:
  - `readSettingsFromDisk()`
  - `readSettingsFromDiskMigrated()`
  - `writeSettingsToDisk(settings)`
  - `persistSettings(changes)`
  - Persistent permission auto-accept policy is stored under `permissionAutoAccept`; execution ownership lives in `lib/permission-auto-accept/`.

## Public exports (settings-helpers.js)
- `createSettingsHelpers(dependencies)`: creates settings helper runtime for settings request/response shaping.
- Returned API:
  - `normalizePwaAppName(value, fallback?)`
  - `sanitizeSettingsUpdate(payload)`
  - `mergePersistedSettings(current, changes)`
  - `formatSettingsResponse(settings)`

## Public exports (settings-normalization-runtime.js)
- `createSettingsNormalizationRuntime(dependencies)`: creates normalization/sanitization runtime for shared settings and tunnel helper logic.
- Returned API:
  - `normalizeDirectoryPath(value)`
  - `normalizePathForPersistence(value)`
  - `normalizeSettingsPaths(input)`
  - `normalizeTunnelBootstrapTtlMs(value)`
  - `normalizeTunnelSessionTtlMs(value)`
  - `normalizeManagedRemoteTunnelHostname(value)`
  - `normalizeManagedRemoteTunnelPresets(value)`
  - `normalizeManagedRemoteTunnelPresetTokens(value)`
  - `isUnsafeSkillRelativePath(value)`
  - `sanitizeTypographySizesPartial(input)`
  - `normalizeStringArray(input)`
  - `sanitizeModelRefs(input, limit)`
  - `sanitizeSkillCatalogs(input)`
  - `sanitizeProjects(input)`

## Public exports (theme-runtime.js)
- `createThemeRuntime(dependencies)`: creates custom theme runtime for on-disk theme discovery and JSON normalization/validation.
- Returned API:
  - `normalizeThemeJson(raw)`
  - `readCustomThemesFromDisk()`

## Public exports (project-directory-runtime.js)
- `createProjectDirectoryRuntime(dependencies)`: creates runtime for request/project directory candidate normalization and validation.
- Returned API:
  - `resolveDirectoryCandidate(value)`
  - `validateDirectoryPath(candidate)`
  - `resolveProjectDirectory(req)`
  - `resolveOptionalProjectDirectory(req)`

## Public exports (config-entity-routes.js)
- `registerConfigEntityRoutes(app, dependencies)`: registers configuration entity routes:
  - Agents: `/api/config/agents/:name` and `/api/config/agents/:name/config`
  - Commands: `/api/config/commands/:name`
  - MCP servers: `/api/config/mcp` and `/api/config/mcp/:name`
  - Snippets: `/api/config/snippets`, `/api/config/snippets/:name`, and `/api/config/snippets/expand`

## Public exports (auth-state-runtime.js)
- `createOpenCodeAuthStateRuntime(dependencies)`: creates runtime for managed OpenCode auth password state and request headers.
- Returned API:
  - `getOpenCodeAuthHeaders()`
  - `isOpenCodeConnectionSecure()`
  - `ensureLocalOpenCodeServerPassword(options?)`

## Public exports (core-routes.js)
- `registerServerStatusRoutes(app, dependencies)`: registers status/system endpoints:
  - `GET /health`
  - `POST /api/system/shutdown`
  - `GET /api/system/info`
 - `registerAuthAndAccessRoutes(app, dependencies)`: registers browser auth/session exchange and API access middleware:
   - `GET /auth/session`
   - `POST /auth/session`
   - `GET /auth/passkey/status`
   - `POST /auth/passkey/authenticate/options`
   - `POST /auth/passkey/authenticate/verify`
   - `POST /auth/passkey/register/options`
   - `POST /auth/passkey/register/verify`
   - `GET /api/passkeys`
   - `DELETE /api/passkeys/:id`
   - `POST /api/auth/reset`
   - `GET /connect`
   - `POST /api/system/probe-url`
   - `app.use('/api', ...)` auth/tunnel guard
- `registerSettingsUtilityRoutes(app, dependencies)`: registers small settings utility endpoints:
  - `GET /api/config/themes`
  - `POST /api/config/reload`
- `registerCommonRequestMiddleware(app, dependencies)`: registers shared request middleware stack:
  - conditional JSON body parser behavior for `/api/*` vs non-API requests
  - URL-encoded parser setup
  - request logging middleware

## Public exports (cli-options.js)
- `parseServeCliOptions(options)`: parses serve CLI flags and environment-derived defaults:
  - Port/host/ui-password
  - Tunnel provider/mode/config/token/hostname
  - Legacy `--tunnel` shorthand normalization

## Public exports (cli-entry-runtime.js)
- `runCliEntryIfMain(dependencies)`: detects direct CLI execution and runs server startup with parsed CLI options.

## Public exports (server-utils-runtime.js)
- `createServerUtilsRuntime(dependencies)`: creates server utility runtime for OpenCode orchestration helpers.
- Returned API:
  - `setOpenCodePort(port)`
  - `waitForOpenCodePort(timeoutMs?)`
  - `buildAugmentedPath()`
  - `parseSseDataPayload(block)`
  - `fetchAgentsSnapshot()`
  - `fetchProvidersSnapshot()`
  - `fetchModelsSnapshot()`
  - `setupProxy(app)`

## Public exports (shutdown-runtime.js)
- `createGracefulShutdownRuntime(dependencies)`: creates graceful shutdown runtime for managed OpenCode and web server teardown sequencing.
- Returned API:
  - `gracefulShutdown(options?)`

## Public exports (server-startup-runtime.js)
- `createServerStartupRuntime(dependencies)`: creates runtime for server bind/startup tunnel and process handler wiring.
- Returned API:
  - `resolveBindHost(host)`
  - `startListeningAndMaybeTunnel(options)`
  - `attachProcessHandlers(options)`

## Public exports (static-routes-runtime.js)
- `createStaticRoutesRuntime(dependencies)`: creates runtime for static dist resolution and static route registration.
- Returned API:
  - `registerStaticRoutes(app)`

## Public exports (feature-routes-runtime.js)
- `createFeatureRoutesRuntime(dependencies)`: creates runtime for main feature route registration orchestration.
- Returned API:
  - `registerRoutes(app, routeDependencies)`

## Public exports (opencode-resolution-runtime.js)
- `createOpenCodeResolutionRuntime(dependencies)`: creates runtime for OpenCode binary/source snapshot resolution.
- Returned API:
  - `getOpenCodeResolutionSnapshot(settings)`: returns configured/resolved OpenCode binary details plus effective managed-launch fields (`launchBinary`, `launchArgs`, `launchWrapperType`) when applicable.

## Public exports (tunnel-wiring-runtime.js)
- `createTunnelWiringRuntime(dependencies)`: creates runtime for tunnel service construction and tunnel route registration.
- Returned API:
  - `initialize(app, initialPort)`

## Public exports (startup-pipeline-runtime.js)
- `createStartupPipelineRuntime(dependencies)`: creates runtime for terminal wiring, proxy/bootstrap scheduling, static route registration, and server startup/listen flow.
- Returned API:
  - `run(options)`

The pipeline binds the OpenChamber listener and publishes its active port
before starting managed OpenCode. The managed custom tool therefore receives
an authoritative loopback callback URL even when OpenChamber binds port `0`.

## Public exports (openchamber-routes.js)
- `registerOpenChamberRoutes(app, dependencies)`: registers OpenChamber endpoints:
  - `GET /api/openchamber/update-check`
  - `POST /api/openchamber/update-install`
  - `GET /api/openchamber/models-metadata`
  - `GET /api/zen/models`

## Public exports (pwa-manifest-routes.js)
- `registerPwaManifestRoute(app, dependencies)`: registers PWA manifest endpoint with dynamic app-name resolution and recent-session shortcuts:
  - `GET /manifest.webmanifest`

## Public exports (project-icon-routes.js)
- `registerProjectIconRoutes(app, dependencies)`: registers project icon routes and owns icon storage/discovery flow:
  - `GET /api/projects/:projectId/icon`
  - `PUT /api/projects/:projectId/icon`
  - `DELETE /api/projects/:projectId/icon`
  - `POST /api/projects/:projectId/icon/discover`

## Public exports (skill-routes.js)
- `registerSkillRoutes(app, dependencies)`: registers skills-related routes:
  - Skills config CRUD and metadata under `/api/config/skills*`
  - Skill rename via `PATCH /api/config/skills/:name` with `{ renameTo }` (directory rename preserves `SKILL.md` body and supporting files; restricted to managed skill roots under `.opencode/skills|skill`, `.claude/skills`, and `.agents/skills`)
  - Skill list responses include authoritative `renamable` derived from the same managed-root policy used by rename
  - Skills catalog listing/source pagination, scan, and install routes
  - Supporting skill file read/write/delete routes
  - Directory resolution prefers an explicit request directory, then soft-falls
    back to the active project / `lastDirectory` so repository-local
    `.agents/skills` and `.opencode/skills` remain discoverable when the client
    omits `directory`. Requests without any project still list user-scoped skills.

## Public exports (proxy.js)
- `registerOpenCodeProxy(app, dependencies)`: registers OpenCode proxy routes and middleware.
- Owns:
  - SSE forwarders: `GET /api/global/event`, `GET /api/event`
    - Downstream heartbeats keep clients and intermediaries alive, while a separate upstream-only stall watchdog closes the downstream response when OpenCode stops producing bytes so clients reconnect instead of trusting synthetic heartbeats indefinitely. Each watchdog reset uses the current load-aware timeout, matching the shared event transport.
  - Session message forwarder: `POST /api/session/:sessionId/message`
  - Interactive OAuth forwarder: `POST /api/provider/:providerID/oauth/callback`
    - Upstream blocks inside this call for the whole browser sign-in (device-code polling or a loopback redirect), so it is exempt from the ordinary request deadline and uses a 15-minute proxy timeout instead of `LONG_REQUEST_TIMEOUT_MS`. All other `/api/provider/*` routes, including `oauth/authorize`, keep the ordinary deadline.
  - Generic `/api/*` forwarding with hop-by-hop header filtering
  - Windows `/session` merge fallback path behavior
  - OpenCode readiness gate for proxied `/api` requests

## Public exports (watcher.js)
- `createOpenCodeWatcherRuntime(dependencies)`: creates global event watcher runtime backed by the shared upstream SSE reader.
- Returned API:
  - `start()`
  - `stop()`
- Behavior:
  - Waits for OpenCode readiness before attaching the watcher.
  - In production wiring, subscribes to the shared global message-stream hub instead of opening its own `/global/event` connection.
  - Can still create its own `/global/event` reader when no shared hub is provided, which keeps module tests and isolated reuse simple.
  - Reuses event-stream parsing, `Last-Event-ID`, stall timeout, and reconnect behavior.
  - Forwards unwrapped global event payloads into notification/session side effects.

## Storage and configuration
- Provider auth: `~/.local/share/opencode/auth.json`.
- User config: `~/.config/opencode/opencode.json`.
- Project config: `<workingDirectory>/.opencode/opencode.json` or `opencode.json`.
- Custom config: `OPENCODE_CONFIG` env var path.
- Rate limit config: `OPENCHAMBER_RATE_LIMIT_MAX_ATTEMPTS`, `OPENCHAMBER_RATE_LIMIT_NO_IP_MAX_ATTEMPTS` env vars.

## Notes for contributors
- This module serves as foundation for OpenCode-related server utilities.
- Route ownership moved to module-level `routes.js`; `index.js` wires dependencies only.
- All file writes include automatic backup before modification.
- Config merging follows priority: custom > project > user.
- UI auth uses scrypt for password hashing with constant-time comparison.
- Tunnel auth treats `host.docker.internal` as local-only when the socket remote IP is private/loopback.