init: 毛孩子计划 小程序 + Go 后端 + 内嵌后台

- pets-fe: 微信原生小程序（首页/计划/记录/报告/社区/引导），
  服务端驱动、无假数据；弹层改用 scroll-view，打开时隐藏自定义 tabBar
- pets-be: Gin + GORM(MySQL, sundynix_ 前缀) + MinIO，统一响应/分页，
  微信 code2session 登录，provider-neutral AI(DeepSeek)，go:embed React 后台
- 修复：分段选择类型不匹配（字符串 vs 数字）导致选不中

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

pets-fe/components/pet-switch/pet-switch.js

@@ -0,0 +1,34 @@
+const store = require('../../utils/store.js');
+
+Component({
+  options: { addGlobalClass: true },
+  data: {
+    pets: [],
+    currentId: 0,
+  },
+  lifetimes: {
+    attached() {
+      this.refresh();
+      this._unsub = store.subscribe(() => this.refresh());
+    },
+    detached() {
+      if (this._unsub) this._unsub();
+    },
+  },
+  methods: {
+    refresh() {
+      this.setData({
+        pets: store.getPets(),
+        currentId: store.currentPetId() || 0,
+      });
+    },
+    onPick(e) {
+      const id = e.currentTarget.dataset.id;
+      store.switchPet(id);
+      this.triggerEvent('change', { id });
+    },
+    onAdd() {
+      this.triggerEvent('add');
+    },
+  },
+});

pets-fe/components/pet-switch/pet-switch.json

@@ -0,0 +1,4 @@
+{
+  "component": true,
+  "usingComponents": {}
+}

pets-fe/components/pet-switch/pet-switch.wxml

@@ -0,0 +1,10 @@
+<scroll-view class="pet-switch" scroll-x="true" enhanced="{{true}}" show-scrollbar="{{false}}">
+  <view wx:for="{{pets}}" wx:key="id"
+        class="pet-chip {{item.id === currentId ? 'active' : ''}}"
+        data-id="{{item.id}}" bindtap="onPick">
+    <view class="mini-avatar">{{item.emoji}}</view>{{item.name}}
+  </view>
+  <view class="pet-chip" bindtap="onAdd">
+    <view class="mini-avatar">＋</view>添加
+  </view>
+</scroll-view>

pets-fe/components/pet-switch/pet-switch.wxss

@@ -0,0 +1,5 @@
+.pet-switch{
+  display:block;white-space:nowrap;width:100%;
+}
+.pet-switch .pet-chip{margin-right:20rpx}
+.pet-switch .pet-chip:last-child{margin-right:0}