perf: reduce re-renders, fix mobile keyboard handling, add chunk load recovery, and improve PATH management (#1028)

* fix: exclude file content from reverted prompt text

Revert and fork now restore only the user's original prompt, not server-injected file content
Uses existing isSyntheticPart helper for type-safe filtering

* fix: keep scrollbar visible when hovering over thumb

* fix: prevent ESC abort from triggering when terminal is focused

* fix: pass directory to permission/question reply calls so approvals actually resolve

* fix: default model selection not responding after Base UI migration

* fix: prevent modal content from shifting and clipping footer buttons

* fix: improve session switching performance and add sub-agent export with prompt collapse

Defer viewport anchor saving to eliminate ~800ms UI freeze when switching sessions
Add export dialog to include sub-agent tasks recursively in markdown export
Add collapse chevron button for expanded user prompts in sticky header

* fix: resolve sidebar scroll and TDZ crash in session sidebar

* perf: reduce CPU overhead and re-renders across chat, layout, and settings

* fix: position collapse button at top of message and prevent ESC abort in terminal

* fix: position collapse button at top and add padding only when expanded

* refactor: extract shared PATH utilities and mobile keyboard hook

* refactor: import shared path-utils in electron, use module-level style constants

- Electron now imports pathLooksUserConfigured/mergePathValues from
  shared path-utils.js instead of inline duplication
- ToolPart collapsedCustomStyle moved from useMemo([]) to module const

* fix: resolve remaining merge conflicts and type errors

- Remove duplicate variable declarations in SessionNodeItem
- Remove orphaned export callback body from conflict resolution
- Fix HelpDialog description -> descriptionKey (i18n rename)

* fix: resolve type-check and lint errors in session-actions.test.ts

- Added missing bun:test type declarations (beforeEach, mock, mock.module)
- Removed unused State import
- Replaced 'as any' casts with proper OpencodeClient and ChildStoreManager types
- Added eslint-disable for unused _ parameter in mock function

* fix PR 1028 export and PATH edge cases

* fix startup retry exhaustion state

* remove opencode package lock change

* fix sub-session rename cancellation

---------

Co-authored-by: Bohdan Triapitsyn <artmore@protonmail.com>

packages/ui/src/lib/i18n/messages/en.ts

@@ -236,6 +236,14 @@ export const dict = {
   'sessions.sidebar.session.export.nothingToExport': 'Nothing to export',
   'sessions.sidebar.session.export.success': 'Session exported',
   'sessions.sidebar.session.export.failedRevealPath': 'Failed to reveal path',
+  'sessions.sidebar.session.export.untitledSubagent': 'Untitled Sub-agent',
+  'sessions.sidebar.session.export.skippedSubtaskSingle': 'Exported session, but skipped {count} sub-agent task that could not be loaded.',
+  'sessions.sidebar.session.export.skippedSubtaskMany': 'Exported session, but skipped {count} sub-agent tasks that could not be loaded.',
+  'sessions.sidebar.session.export.dialog.title': 'Export Markdown',
+  'sessions.sidebar.session.export.dialog.descriptionSingle': 'This session has {count} sub-agent task. Include it in the export?',
+  'sessions.sidebar.session.export.dialog.descriptionMany': 'This session has {count} sub-agent tasks. Include them in the export?',
+  'sessions.sidebar.session.export.dialog.includeSubtasks': 'Include sub-agent tasks',
+  'sessions.sidebar.session.export.dialog.confirm': 'Export',
   'sessions.sidebar.session.status.active': 'Session active',
   'sessions.sidebar.session.status.unread': 'Unread updates',
   'sessions.sidebar.session.status.pinned': 'Pinned session',
@@ -1958,6 +1966,10 @@ export const dict = {
   'onboarding.desktopRecovery.common.useRemote': 'Use Remote',
   'onboarding.desktopRecovery.actions.retrying': 'Retrying…',
   'onboarding.desktopRecovery.actions.retryConnection': 'Retry Connection',
+  'startup.initRecovery.title': 'Startup failed',
+  'startup.initRecovery.description': 'OpenChamber could not finish initialization. Check that the server is running, then retry.',
+  'startup.initRecovery.retry': 'Retry',
+  'startup.initRecovery.retrying': 'Retrying…',
   'onboarding.desktopRecovery.placeholders.remoteServer': 'the remote server',
   'onboarding.desktopRecovery.placeholders.unknownServer': 'unknown',
   'vscodeLayout.title.chat': 'Chat',