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/services/exercise.js

@@ -0,0 +1,62 @@
+// 业务服务层：直接映射后端 REST 接口字段，不做多余转换。
+const { request } = require('../utils/request');
+
+// 将参数对象序列化为 query string（跳过空值）
+function buildQuery(params) {
+  const qs = Object.keys(params || {})
+    .filter(k => params[k] !== '' && params[k] !== undefined && params[k] !== null)
+    .map(k => encodeURIComponent(k) + '=' + encodeURIComponent(params[k]))
+    .join('&');
+  return qs ? '?' + qs : '';
+}
+
+// 1) 动作列表（支持多维筛选与排序）
+function listExercises(params = {}) {
+  return request({ url: '/api/exercises' + buildQuery(params) });
+}
+
+// 2) 动作详情
+function getExercise(id) {
+  return request({ url: '/api/exercises/' + encodeURIComponent(id) });
+}
+
+// 3) 分类维度枚举
+function getCategories(type) {
+  return request({ url: '/api/categories/' + encodeURIComponent(type) });
+}
+
+// 4) 智能推荐
+function recommend(params = {}) {
+  return request({ url: '/api/recommend' + buildQuery(params) });
+}
+
+// 5) 训练组合列表
+function listCollections() {
+  return request({ url: '/api/collections' });
+}
+
+// 5) 训练组合下的动作
+function getCollectionExercises(slug, params = {}) {
+  return request({ url: '/api/collections/' + encodeURIComponent(slug) + '/exercises' + buildQuery(params) });
+}
+
+// 6) 搜索
+function search(q) {
+  return request({ url: '/api/search?q=' + encodeURIComponent(q) });
+}
+
+// 7) 统计概览
+function getStats() {
+  return request({ url: '/api/stats' });
+}
+
+module.exports = {
+  listExercises,
+  getExercise,
+  getCategories,
+  recommend,
+  listCollections,
+  getCollectionExercises,
+  search,
+  getStats
+};