feat: add conversation management, persistence, and mobile app spec

Major enhancements to voice assistant with conversation persistence
and mobile app planning:

- Add conversation management with multiple active conversations
- Implement conversation persistence (save/load from disk)
- Add conversation selector UI for switching between conversations
- Enhance agent prompt with per-conversation tmux sessions
- Add mobile app technical specification (React Native + Expo)
- Improve UI with active processes view and agent stream
- Add ACP (Agent Control Protocol) server implementation

Mobile spec details:
- React Native with Expo SDK 54+
- NativeWind v5 for styling
- Share Zod schemas/types from server
- Android in-call experience (InCallManager)
- Direct WebSocket connection via Tailscale
- Same audio quality as web prototype

🤖 Generated with [Claude Code](https://claude.com/claude-code)
via [Happy](https://happy.engineering)

Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

packages/voice-assistant/package.json

@@ -10,11 +10,15 @@
     "build": "npm run build:ui && npm run build:server",
     "start": "NODE_ENV=production node dist/server/index.js",
     "typecheck": "tsc --noEmit && tsc -p tsconfig.server.json --noEmit",
+    "test": "vitest run",
+    "test:watch": "vitest",
+    "test:ui": "vitest --ui",
     "test:e2e": "playwright test",
     "test:e2e:ui": "playwright test --ui",
     "test:e2e:mobile": "playwright test --project='Mobile Chrome'"
   },
   "dependencies": {
+    "@agentclientprotocol/sdk": "^0.4.9",
     "@ai-sdk/openai": "^2.0.52",
     "@deepgram/sdk": "^3.4.0",
     "@modelcontextprotocol/sdk": "^1.20.1",
@@ -42,12 +46,14 @@
     "@types/uuid": "^9.0.7",
     "@types/ws": "^8.5.8",
     "@vitejs/plugin-react": "^4.2.0",
+    "@vitest/ui": "^3.2.4",
     "concurrently": "^8.2.2",
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
     "tsx": "^4.6.0",
     "typescript": "^5.2.2",
     "vite": "^7.1.10",
-    "vite-plugin-static-copy": "^3.1.4"
+    "vite-plugin-static-copy": "^3.1.4",
+    "vitest": "^3.2.4"
   }
 }