feat: require couple binding and refine miniapp settings

Gate record features and storage entry points with invitation guidance; enforce record access in the backend. Add homepage greetings, right-swipe profile dismissal, and move the smoking switch to settings. Simplify API base configuration and remove the unused legacy tab bar component.

weapp/pages/settings/settings.wxml

@@ -24,6 +24,12 @@
       <text class="j-link">›</text>
     </view>
 
+    <view class="j-profile-setting">
+      <view class="setting-info"><view class="j-small-title">抽烟记录</view><view class="j-caption">默认开启，关闭后不在打卡页显示，已有记录保留</view></view>
+      <switch wx:if="{{smokingKnown}}" checked="{{smokingVisible}}" disabled="{{smokingSaving}}" color="#667E75" bindchange="toggleSmoking" />
+      <text wx:elif="{{smokingError}}" class="j-link" bindtap="loadSmokingPreference">重试</text><text wx:else class="j-caption">加载中</text>
+    </view>
+
     <view class="section-heading">关系与账号</view>
     <view class="j-profile-setting" bindtap="deleteAccount"><view class="setting-info"><view class="j-small-title" style="color:#B74768">注销账号</view><view class="j-caption">{{hasPartner ? '请先完成情侣解绑，再注销账号' : '确认后删除账号及全部个人数据'}}</view></view><text class="j-link">›</text></view>
     <!-- 操作记录 -->