chore: freeze guide and explain update

src/pages/hall/detail.vue

@@ -2,7 +2,9 @@
   <GuidePageFrame
     :active-tab="activeTopTab"
     variant="static"
+    show-back
     @tab-change="handleTopTabChange"
+    @back="handleBack"
   >
     <view class="detail-page">
       <scroll-view class="content" scroll-y>
@@ -47,8 +49,12 @@
 
       <!-- 底部操作栏 -->
       <view class="action-bar">
-        <view class="action-btn primary" @tap="handleNavigate">
-          <text class="btn-text">查看三维位置</text>
+        <view
+          class="action-btn primary"
+          :class="{ disabled: !hall.location?.poiId }"
+          @tap="handleNavigate"
+        >
+          <text class="btn-text">{{ hall.location?.actionText || '暂无位置' }}</text>
         </view>
       </view>
     </view>
@@ -84,7 +90,7 @@ const hall = ref<HallDetailViewModel>({
   id: '',
   name: '展厅内容',
   floorLabel: '楼层待补充',
-  description: '该空间介绍待 SGS 场景设置或 CMS 内容补充。',
+  description: '该展厅暂无介绍文案。',
   image: '/static/hall-placeholder.jpg',
   exhibitCount: 0,
   area: '待补充'
@@ -140,6 +146,17 @@ const handleNavigate = async () => {
 const handleTopTabChange = (tab: GuideTopTab) => {
   navigateToGuideTopTab(tab)
 }
+
+const handleBack = () => {
+  uni.navigateBack({
+    delta: 1,
+    fail: () => {
+      uni.reLaunch({
+        url: '/pages/index/index?tab=explain'
+      })
+    }
+  })
+}
 </script>
 
 <style scoped lang="scss">