feat: initialize Ballet Island 微信小程序 with basic structure and functionality

- Add project configuration for WeChat mini program.
- Create skills lock file for Taroify integration.
- Set up app configuration and styles.
- Implement main app component and index page with welcome message.
- Add health check service to verify backend readiness.
- Configure TypeScript settings and global types.

miniprogram/project.config.json

@@ -0,0 +1,13 @@
+{
+  "description": "Ballet Island 微信小程序",
+  "miniprogramRoot": "dist/",
+  "projectname": "ballet-island",
+  "appid": "wx6dfbf1021db8aee0",
+  "compileType": "miniprogram",
+  "setting": {
+    "es6": false,
+    "minified": true,
+    "postcss": false,
+    "urlCheck": true
+  }
+}