feat: init fitness-coach (backend + miniprogram)

- backend: NestJS service with exercise/plan data
- miniprogram: WeChat mini program client
- exclude node_modules, dist, runtime data-store, local env

miniprogram/app.json

@@ -0,0 +1,19 @@
+{
+  "pages": [
+    "pages/index/index",
+    "pages/category/category",
+    "pages/recommend/recommend",
+    "pages/detail/detail",
+    "pages/collection/collection",
+    "pages/collection-detail/collection-detail",
+    "pages/search/search"
+  ],
+  "window": {
+    "navigationStyle": "custom",
+    "backgroundColor": "#0E1110",
+    "navigationBarTextStyle": "white",
+    "navigationBarTitleText": "FITCOACH"
+  },
+  "style": "v2",
+  "sitemapLocation": "sitemap.json"
+}