fix: restore desktop startup and align tool previews with SDK updates

Add reflect-metadata bootstrap so desktop sidecar no longer crashes on startup.
Update SDK v1.4 compatibility for model variant and diff payload handling.
Unify write/edit/apply patch expanded previews and hide write success output noise.

packages/ui/src/sync/event-reducer.ts

@@ -1,6 +1,5 @@
 import type {
   Event,
-  FileDiff,
   Message,
   Part,
   PermissionRequest,
@@ -11,7 +10,7 @@ import type {
   Todo,
 } from "@opencode-ai/sdk/v2/client"
 import { Binary } from "./binary"
-import type { GlobalState, State } from "./types"
+import type { FileDiff, GlobalState, State } from "./types"
 import { dropSessionCaches } from "./session-cache"
 import { stripSessionDiffSnapshots } from "./sanitize"
 import { syncDebug } from "./debug"

packages/ui/src/sync/sanitize.ts

@@ -1,8 +1,9 @@
 // ---------------------------------------------------------------------------
 // Payload sanitization — strip oversized diff snapshot fields client-side.
 //
-// OpenCode session objects carry summary.diffs[].before/after with full file
-// contents. The UI never uses these fields but they waste browser memory and
+// OpenCode session/message snapshots may carry large full-content diff fields
+// (legacy before/after or from/to). The UI never uses these fields but they
+// waste browser memory and
 // can crash tabs for large sessions.
 //
 // Applied at two points:
@@ -19,6 +20,8 @@ type DiffEntry = {
   deletions?: number
   before?: string
   after?: string
+  from?: string
+  to?: string
 }
 
 type SessionSummary = {
@@ -26,16 +29,24 @@ type SessionSummary = {
   [key: string]: unknown
 }
 
-/** Strip before/after from summary.diffs on a session object */
+/** Strip oversized snapshot fields from summary.diffs on a session object */
 export function stripSessionDiffSnapshots(session: Session): Session {
   const summary = (session as { summary?: SessionSummary }).summary
   if (!summary?.diffs || !Array.isArray(summary.diffs)) return session
 
   let changed = false
   const stripped = summary.diffs.map((d) => {
-    if (d && (typeof d.before === "string" || typeof d.after === "string")) {
-      // eslint-disable-next-line @typescript-eslint/no-unused-vars
-      const { before: _before, after: _after, ...rest } = d
+    if (d && (
+      typeof d.before === "string"
+      || typeof d.after === "string"
+      || typeof d.from === "string"
+      || typeof d.to === "string"
+    )) {
+      const rest = { ...d }
+      delete rest.before
+      delete rest.after
+      delete rest.from
+      delete rest.to
       changed = true
       return rest
     }
@@ -46,16 +57,24 @@ export function stripSessionDiffSnapshots(session: Session): Session {
   return { ...session, summary: { ...summary, diffs: stripped } } as Session
 }
 
-/** Strip before/after from summary.diffs on a message object */
+/** Strip oversized snapshot fields from summary.diffs on a message object */
 export function stripMessageDiffSnapshots(message: Message): Message {
   const summary = (message as { summary?: SessionSummary }).summary
   if (!summary?.diffs || !Array.isArray(summary.diffs)) return message
 
   let changed = false
   const stripped = summary.diffs.map((d) => {
-    if (d && (typeof d.before === "string" || typeof d.after === "string")) {
-      // eslint-disable-next-line @typescript-eslint/no-unused-vars
-      const { before: _before, after: _after, ...rest } = d
+    if (d && (
+      typeof d.before === "string"
+      || typeof d.after === "string"
+      || typeof d.from === "string"
+      || typeof d.to === "string"
+    )) {
+      const rest = { ...d }
+      delete rest.before
+      delete rest.after
+      delete rest.from
+      delete rest.to
       changed = true
       return rest
     }

packages/ui/src/sync/session-cache.ts

@@ -1,5 +1,4 @@
 import type {
-  FileDiff,
   Message,
   Part,
   PermissionRequest,
@@ -7,6 +6,7 @@ import type {
   SessionStatus,
   Todo,
 } from "@opencode-ai/sdk/v2/client"
+import type { FileDiff } from "./types"
 
 type SessionCache = {
   session_status: Record<string, SessionStatus | undefined>

packages/ui/src/sync/session-ui-store.ts

@@ -1099,7 +1099,7 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
     const messages = getSyncMessages(sessionId, directory)
     for (let i = messages.length - 1; i >= 0; i -= 1) {
       const message = messages[i] as Message & {
-        model?: { providerID?: string; modelID?: string }
+        model?: { providerID?: string; modelID?: string; variant?: string }
         variant?: string
         mode?: string
       }
@@ -1116,8 +1116,9 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
       const agent = typeof message.agent === "string" && message.agent.trim().length > 0
         ? message.agent
         : (typeof message.mode === "string" && message.mode.trim().length > 0 ? message.mode : undefined)
-      const variant = typeof message.variant === "string" && message.variant.trim().length > 0
-        ? message.variant
+      const variantCandidate = message.model?.variant ?? message.variant
+      const variant = typeof variantCandidate === "string" && variantCandidate.trim().length > 0
+        ? variantCandidate
         : undefined
 
       return { agent, providerID, modelID, variant }

packages/ui/src/sync/types.ts

@@ -2,7 +2,6 @@ import type {
   Agent,
   Command,
   Config,
-  FileDiff,
   LspStatus,
   McpStatus,
   Message,
@@ -19,6 +18,15 @@ import type {
   VcsInfo,
 } from "@opencode-ai/sdk/v2/client"
 
+export type FileDiff = {
+  file?: string
+  status?: string
+  additions?: number
+  deletions?: number
+  patch?: string
+  [key: string]: unknown
+}
+
 export type ProjectMeta = {
   name?: string
   icon?: {