fix(sharedWork): replace back nav with uni.reLaunch

remove the page stack navigation check, directly relaunch to the index page, add a fail toast for reLaunch failures

src/pages-aigc/sharedWork/sharedWork.vue

@@ -106,13 +106,10 @@ const openAigcHome = () => {
 };
 
 const handleBack = () => {
-  const pages = getCurrentPages();
-  if (pages.length > 1) {
-    uni.navigateBack();
-    return;
-  }
-
-  openAigcHome();
+  uni.reLaunch({
+    url: "/pages/index/index",
+    fail: () => showToast("返回首页失败"),
+  });
 };
 
 const handleCreateOwn = async () => {