chore: remove unused deps and declare missing ones

Knip-driven cleanup across all workspaces:

Removed (verified zero imports):
- root: @anthropic-ai/claude-agent-sdk, @modelcontextprotocol/sdk,
  expo, react, react-native, react-dom (duplicates of workspace deps)
- server: @ai-sdk/openai, @deepgram/sdk, express-basic-auth,
  fast-uri, mnemonic-id, tiny-invariant, playwright
- app: @expo/vector-icons, @getpaseo/server,
  @react-navigation/bottom-tabs, @react-navigation/elements,
  base64-js, react-native-css, expo-av, expo-font, expo-symbols,
  expo-web-browser, react-native-permissions,
  react-native-popover-view, react-native-securerandom
- cli: @getpaseo/relay
- desktop: @getpaseo/cli
- relay: @cloudflare/workers-types
- website: tailwindcss (provided by @tailwindcss/vite)

Declared (previously hoisted, now explicit):
- root: @types/ws, playwright, ws (used by scripts/)
- server: @mariozechner/pi-ai, @mariozechner/pi-agent-core
- app: expo-asset, qrcode, @types/qrcode, tiny-invariant,
  @xterm/headless, dotenv, jsdom
- cli: vitest
- desktop: vitest

Also removes the stray `/app.json` (obsolete, overridden by
packages/app/app.config.js).

package.json

@@ -87,23 +87,17 @@
     "release:minor": "npm run release:check && npm run version:all:minor && npm run release:publish && npm run release:push",
     "release:major": "npm run release:check && npm run version:all:major && npm run release:publish && npm run release:push"
   },
-  "dependencies": {
-    "@anthropic-ai/claude-agent-sdk": "^0.2.11",
-    "@modelcontextprotocol/sdk": "^1.27.1",
-    "expo": "~54.0.33",
-    "react": "19.1.0",
-    "react-native": "0.81.5"
-  },
   "devDependencies": {
+    "@types/ws": "^8.5.14",
     "concurrently": "^9.2.1",
     "get-port-cli": "^3.0.0",
     "knip": "^5.82.1",
     "oxfmt": "0.46.0",
     "oxlint": "1.61.0",
     "patch-package": "^8.0.1",
-    "react": "19.1.0",
-    "react-dom": "19.1.0",
-    "typescript": "^5.9.3"
+    "playwright": "^1.56.1",
+    "typescript": "^5.9.3",
+    "ws": "^8.20.0"
   },
   "overrides": {
     "lightningcss": "1.30.1",