feat(deps): add Valtio and XState for Phase 2

- Add valtio for Proxy-based state management
- Add xstate and @xstate/react for state machines
- Create domains directory structure (chat, hands, intelligence, skills)
- Create shared directory for common utilities

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

desktop/package.json

@@ -31,6 +31,7 @@
   "dependencies": {
     "@tauri-apps/api": "^2",
     "@tauri-apps/plugin-opener": "^2",
+    "@xstate/react": "^6.1.0",
     "clsx": "^2.1.1",
     "date-fns": "^4.1.0",
     "framer-motion": "^12.36.0",
@@ -42,6 +43,8 @@
     "tailwind-merge": "^3.5.0",
     "tweetnacl": "^1.0.3",
     "uuid": "^11.0.0",
+    "valtio": "^2.3.1",
+    "xstate": "^5.28.0",
     "zustand": "^5.0.11"
   },
   "devDependencies": {