fix: 修复评论/资料/导航胶囊/宠物档案/定位等多处问题，补全相关云函数

- 新增 addComment/getComments/getFollowList/followUser/getUser/updateProfile/updatePet/deletePet 云函数并完成部署
- 统一通过 app.globalData.navBarInfo 避让系统胶囊按钮（编辑资料/编辑宠物等页面保存按钮被遮挡问题）
- 编辑资料页所在城市改为省份 picker 选择
- 修复"我的"页动态为空（getUserPosts 应传 openid 而非数据库 _id）
- 重构编辑宠物页：品种改用 picker 滚轮（替代有数量上限的 actionSheet），标签改用 selectedTagSet 映射 + 自定义标签输入（5字以内、仅中英文/数字、最多8个）
- 接通宠物保存/删除真实云函数调用并同步本地缓存
- 移除 feed 页对不存在的 getStories 云函数调用，修复模拟器卡死
- 移除 post 页对不存在的 wx.reverseGeocoder API 的调用
- 统一扩展 AppGlobalData 类型并修正所有 getApp 调用的泛型，解决 TS 报错

miniprogram/components/post-card/post-card.wxml

@@ -1,11 +1,11 @@
 <view class="post-card" bindtap="onCardTap">
   <!-- 作者头部 -->
   <view class="post-header">
-    <view class="post-avatar" style="background: {{avatarGradient}}" bindtap="onAuthorTap" catchtap="onAuthorTap">
-      <text>{{post.author.nickName[0] || '?'}}</text>
+    <view class="post-avatar" style="background: {{avatarGradient}}" catchtap="onAuthorTap">
+      <text>{{post.author && post.author.nickName ? post.author.nickName[0] : '?'}}</text>
     </view>
     <view class="post-meta">
-      <text class="post-username">{{post.author.nickName}}</text>
+      <text class="post-username">{{post.author && post.author.nickName ? post.author.nickName : '匿名用户'}}</text>
       <view class="post-loc" wx:if="{{post.location}}">
         <text class="loc-icon">📍</text>
         <text class="loc-text">{{post.location.name}}</text>
@@ -17,19 +17,19 @@
   <!-- 图片 -->
   <view wx:if="{{post.images && post.images.length > 0}}" class="post-images-wrap">
     <!-- 单图全宽 -->
-    <view wx:if="{{post.images.length === 1}}" class="post-img-single">
+    <view wx:if="{{post.images && post.images.length === 1}}" class="post-img-single">
       <image
         class="img-single"
         src="{{post.images[0]}}"
         mode="aspectFill"
         lazy-load="true"
-        bindtap="onImageTap"
+        catchtap="onImageTap"
         data-idx="0"
       />
       <view wx:if="{{post.mood}}" class="post-tag-chip">{{post.mood}}</view>
     </view>
     <!-- 多图网格 -->
-    <view wx:else class="post-img-grid post-img-grid-{{post.images.length > 3 ? 'multi' : post.images.length}}">
+    <view wx:else class="post-img-grid {{imageGridClass}}">
       <image
         wx:for="{{post.images}}"
         wx:key="index"
@@ -38,7 +38,7 @@
         src="{{item}}"
         mode="aspectFill"
         lazy-load="true"
-        bindtap="onImageTap"
+        catchtap="onImageTap"
         data-idx="{{index}}"
       />
     </view>
@@ -55,15 +55,15 @@
 
     <!-- 操作栏 -->
     <view class="post-actions">
-      <view class="action-btn {{post.isLiked ? 'liked' : ''}}" bindtap="onLike" catchtap="onLike">
+      <view class="action-btn {{post.isLiked ? 'liked' : ''}}" catchtap="onLike">
         <text class="action-icon">{{post.isLiked ? '❤️' : '🤍'}}</text>
         <text class="action-count">{{likeCount}}</text>
       </view>
-      <view class="action-btn" bindtap="onComment" catchtap="onComment">
+      <view class="action-btn" catchtap="onComment">
         <text class="action-icon">💬</text>
-        <text class="action-count">{{post.commentCount}}</text>
+        <text class="action-count">{{post.commentCount || 0}}</text>
       </view>
-      <view class="action-btn" bindtap="onShare" catchtap="onShare">
+      <view class="action-btn" catchtap="onShare">
         <text class="action-icon">↗</text>
         <text class="action-count">转发</text>
       </view>