feat(app): initialize uni-app with routing, stores, and infrastructure

- Vue 3 + TypeScript + Pinia + SCSS
- 3-tab navigation (home, booking, profile) + 11 sub-pages
- HTTP client with JWT auth, request interceptors
- Pinia stores: user (auth, profile, memberships), studio, booking
- Utility functions: price formatting, date helpers
- WeChat login helper
- All pages as stubs ready for implementation

packages/app/package.json

@@ -0,0 +1,32 @@
+{
+  "name": "@mp-pilates/app",
+  "version": "0.1.0",
+  "private": true,
+  "scripts": {
+    "dev:mp-weixin": "uni -p mp-weixin",
+    "build:mp-weixin": "uni build -p mp-weixin",
+    "type-check": "vue-tsc --noEmit"
+  },
+  "dependencies": {
+    "@dcloudio/uni-app": "3.0.0-4060620250520001",
+    "@dcloudio/uni-app-plus": "3.0.0-4060620250520001",
+    "@dcloudio/uni-components": "3.0.0-4060620250520001",
+    "@dcloudio/uni-h5": "3.0.0-4060620250520001",
+    "@dcloudio/uni-mp-weixin": "3.0.0-4060620250520001",
+    "@mp-pilates/shared": "workspace:*",
+    "pinia": "^2.1.7",
+    "vue": "^3.4.0"
+  },
+  "devDependencies": {
+    "@dcloudio/types": "^3.4.0",
+    "@dcloudio/uni-automator": "3.0.0-4060620250520001",
+    "@dcloudio/uni-cli-shared": "3.0.0-4060620250520001",
+    "@dcloudio/uni-stacktracey": "3.0.0-4060620250520001",
+    "@dcloudio/vite-plugin-uni": "3.0.0-4060620250520001",
+    "@types/node": "^20.0.0",
+    "typescript": "^5.4.0",
+    "vite": "^5.4.0",
+    "vue-tsc": "^2.0.0",
+    "sass": "^1.77.0"
+  }
+}