feat: update TopNavBar and shared work page navigation

Add leftAction prop to TopNavBar to support back or home left navigation actions, update left icon accordingly. Add optional chaining to shareDetail.templateName to prevent errors. Modify sharedWork page to use home left action and update back handler to use direct home reLaunch.

src/pages-aigc/sharedWork/sharedWork.vue

@@ -1,8 +1,9 @@
 <template>
   <view class="shared-work-page">
     <view class="shared-work-nav">
-      <TopNavBar :title="shareDetail.templateName || '旅行作品'" background="#fff" title-color="#173a5f"
-        back-icon-color="#173a5f" :align-with-menu-button="true" :z-index="3" @back="handleBack" />
+      <TopNavBar :title="shareDetail?.templateName || '旅行作品'" background="#fff" title-color="#173a5f"
+        back-icon-color="#173a5f" left-action="home" :align-with-menu-button="true" :z-index="3"
+        @back="openAppHome" />
     </view>
 
     <view class="shared-work-scroll">
@@ -106,14 +107,11 @@ const openAigcHome = () => {
   });
 };
 
-const handleBack = () => {
-  const pages = getCurrentPages();
-  if (pages.length > 1) {
-    uni.navigateBack();
-    return;
-  }
-
-  openAigcHome();
+const openAppHome = () => {
+  uni.reLaunch({
+    url: "/pages/index/index",
+    fail: () => showToast("打开首页失败"),
+  });
 };
 
 const handleCreateOwn = async () => {