feat: remove legacy OpenCode runtime

Cut product flows over to Coding/Pi and retain only the migration-owned v1 boundary. Promote supported native optional packages because electron-builder omitted pnpm transitive optional closure from the packaged ASAR.

electron/main/ipc-handlers.ts

@@ -1,9 +1,8 @@
 /**
  * IPC Handlers
- * Registers the renderer channels used by the opencode-first desktop app.
+ * Registers the renderer channels used by the desktop app.
  */
 import { app, BrowserWindow, dialog, ipcMain, shell } from 'electron';
-import type { OpencodeManager } from '../opencode/manager';
 import { registerHostApiProxyHandlers } from './ipc/host-api-proxy';
 import { registerTranscriptExportHandler } from './ipc/transcript-export';
 import { applyProxySettings } from './proxy';
@@ -184,7 +183,6 @@ async function handleUnifiedProvider(action: string, payload: unknown): Promise<
 
 async function handleUnifiedRequest(
   request: UnifiedRequest,
-  opencodeManager: OpencodeManager,
 ): Promise<UnifiedResponse> {
   const id = request.id;
   const module = request.module || '';
@@ -198,11 +196,6 @@ async function handleUnifiedRequest(
       return unsupported(id, module, action);
     }
 
-    if (module === 'opencode') {
-      if (action === 'status') return ok(id, opencodeManager.getStatus());
-      return unsupported(id, module, action);
-    }
-
     if (module === 'settings') {
       if (action === 'getAll') return ok(id, await getAllSettings());
       if (action === 'get') {
@@ -241,9 +234,6 @@ async function handleUnifiedRequest(
 }
 
 export function registerIpcHandlers(
-  _legacyRuntimeManager: unknown,
-  opencodeManager: OpencodeManager,
-  _legacyMarketplaceService: unknown,
   mainWindow: BrowserWindow,
   lifecycle?: BackgroundLifecycleController,
   hostApiContext?: HostApiContext,
@@ -262,7 +252,7 @@ export function registerIpcHandlers(
     rendererWebContents.on('destroyed', releaseRendererLeases);
   }
   ipcMain.handle('app:request', async (_event, request: UnifiedRequest) => (
-    handleUnifiedRequest(request, opencodeManager)
+    handleUnifiedRequest(request)
   ));
 
   ipcMain.handle('app:version', () => app.getVersion());
@@ -276,15 +266,6 @@ export function registerIpcHandlers(
   });
   ipcMain.handle('app:performance', () => collectPerformanceSnapshot(lifecycle));
 
-  ipcMain.handle('opencode:status', () => opencodeManager.getStatus());
-  ipcMain.handle('opencode:start', () => opencodeManager.start());
-  ipcMain.handle('opencode:stop', async () => {
-    await opencodeManager.stop();
-    return opencodeManager.getStatus();
-  });
-  ipcMain.handle('opencode:restart', () => opencodeManager.restart());
-  ipcMain.handle('opencode:health', () => opencodeManager.checkHealth());
-
   ipcMain.handle('lifecycle:activity', (_event, activity: DesktopActivity) => {
     const nextActivity = activity && typeof activity === 'object'
       ? activity