排序铁律: 主分支强制置顶(parent_task_id为空优先)+子分支按created_at正序

track-uniapp/src/pages/scan/components/WorkspaceArea.vue

@@ -132,6 +132,13 @@ export default {
         }
       };
       if (this.product) walk(this.product.task_tree);
+      result.sort((a, b) => {
+        const aIsMain = !a.parent_task_id;
+        const bIsMain = !b.parent_task_id;
+        if (aIsMain && !bIsMain) return -1;
+        if (!aIsMain && bIsMain) return 1;
+        return new Date(a.created_at) - new Date(b.created_at);
+      });
       return result;
     },
     lockedTask() { return this.focusTasks.find(t => t.id === this.lockedTaskId) || null; },