feat: chat integration, tenant admin spec, backend chat service, miniprogram updates, DEMO moved to tmp, XCX-TEST removed, migrations & docs

tmp/DEMO-miniprogram/miniprogram/custom-tab-bar/index.wxml

@@ -0,0 +1,17 @@
+<!-- 自定义 tabBar — 支持 2/3 按钮动态布局 -->
+<view class="tab-bar tab-bar--{{tabCount}}">
+  <view
+    wx:for="{{tabs}}"
+    wx:key="key"
+    class="tab-bar-item {{active === item.key ? 'tab-bar-item--active' : ''}}"
+    bindtap="onTap"
+    data-key="{{item.key}}"
+  >
+    <image
+      class="tab-bar-icon"
+      src="{{active === item.key ? item.activeIcon : item.icon}}"
+      mode="aspectFit"
+    />
+    <text class="tab-bar-label">{{item.label}}</text>
+  </view>
+</view>