fix(annotation): 标注配置可视化编辑器根据父节点类型限制子标签选项

根据选中节点类型动态过滤"添加子节点"和"添加同级节点"下拉选项：
- 标注控件（如 Choices/RectangleLabels）仅允许添加对应的子标签（Choice/Label）
- 无子节点的控件（如 TextArea/Rating）和数据对象标签禁用添加子节点
- Choice 节点允许嵌套 Choice（支持 Taxonomy 层级结构）
- View 容器允许添加所有标签类型但排除裸子标签

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/pages/DataAnnotation/components/TemplateConfigurationTreeEditor.tsx

@@ -566,6 +566,76 @@ const TemplateConfigurationTreeEditor = ({
     return options;
   }, [objectOptions, controlOptions]);
 
+  type TagOptionGroup = { label: string; options: { value: string; label: string }[] };
+
+  const getAllowedChildOptions = useCallback(
+    (node: XmlNode): TagOptionGroup[] => {
+      if (!config) return tagOptions;
+
+      const controlConfig = config.controls?.[node.tag];
+      const objectConfig = config.objects?.[node.tag];
+
+      // Control with child_tag: only allow that specific child tag
+      if (controlConfig?.requires_children && controlConfig.child_tag) {
+        const childTag = controlConfig.child_tag;
+        return [
+          {
+            label: "子标签",
+            options: [
+              {
+                value: childTag,
+                label: COMMON_TAG_DISPLAY_NAMES[childTag] || childTag,
+              },
+            ],
+          },
+        ];
+      }
+
+      // Control without requires_children: no children allowed
+      if (controlConfig && !controlConfig.requires_children) {
+        return [];
+      }
+
+      // Object tag: no children
+      if (objectConfig) {
+        return [];
+      }
+
+      // Child tag: Choice allows nested Choice (for Taxonomy), others don't
+      if (CHILD_TAGS.includes(node.tag)) {
+        if (node.tag === "Choice") {
+          return [
+            {
+              label: "子标签",
+              options: [
+                {
+                  value: "Choice",
+                  label: COMMON_TAG_DISPLAY_NAMES.Choice || "Choice",
+                },
+              ],
+            },
+          ];
+        }
+        return [];
+      }
+
+      // View or other containers: show all except bare child tags
+      return tagOptions.filter((group) => group.label !== "子标签");
+    },
+    [config, tagOptions]
+  );
+
+  const childTagOptions = useMemo(
+    () => getAllowedChildOptions(selectedNode),
+    [getAllowedChildOptions, selectedNode]
+  );
+
+  const siblingTagOptions = useMemo(() => {
+    const { parent } = findNodeWithParent(tree, selectedNode.id);
+    if (!parent) return [];
+    return getAllowedChildOptions(parent);
+  }, [tree, selectedNode, getAllowedChildOptions]);
+
   const getTagDisplayName = useCallback(
     (tag: string) => {
       if (config?.objects?.[tag]) return getObjectDisplayName(tag);
@@ -796,21 +866,21 @@ const TemplateConfigurationTreeEditor = ({
           <div className="grid grid-cols-2 gap-2">
             <Select
               placeholder="添加子节点"
-              options={tagOptions}
+              options={childTagOptions}
               value={null}
               onChange={(value) => {
                 handleAddNode(value, "child");
               }}
-              disabled={isStructureLocked}
+              disabled={isStructureLocked || childTagOptions.length === 0}
             />
             <Select
               placeholder="添加同级节点"
-              options={tagOptions}
+              options={siblingTagOptions}
               value={null}
               onChange={(value) => {
                 handleAddNode(value, "sibling");
               }}
-              disabled={isStructureLocked || selectedNode.id === tree.id}
+              disabled={isStructureLocked || selectedNode.id === tree.id || siblingTagOptions.length === 0}
             />
             <Button
               danger