feat: skill清空逻辑。因为后端接口不支持取消选择skill，所以暂时禁用取消选择按钮

frontend/src/components/workspace/iframe-test-panel.tsx

@@ -313,6 +313,23 @@ export function IframeTestPanel() {
             >
               📦 模拟 selectedSkills（数组 message）
             </Button>
+            <Button
+              size="sm"
+              className="w-full bg-slate-50 text-xs text-slate-700 hover:bg-slate-100"
+              variant="ghost"
+              onClick={() => {
+                window.postMessage(
+                  {
+                    type: POST_MESSAGE_TYPES.SELECT_SKILLS,
+                    selectedSkills: [],
+                  },
+                  "*",
+                );
+                addLog("模拟宿主页 → selectedSkills []");
+              }}
+            >
+              🧹 模拟 selectedSkills（空数组）
+            </Button>
             <Button
               size="sm"
               className="w-full bg-orange-50 text-xs text-orange-700 hover:bg-orange-100"

frontend/src/components/workspace/input-box.tsx

@@ -648,7 +648,7 @@ function IframeSkillDialogButton({
   selectedSkills: Array<{ skill_id: string; title: string }>;
   isBootstrapping: boolean;
   openSkillDialog: () => void;
-  clearSkill: () => void;
+  clearSkill: (skillId?: string) => void;
 }) {
   const { t } = useI18n();
 
@@ -683,13 +683,14 @@ function IframeSkillDialogButton({
           {selectedSkills.map((skill, index) => (
             <Tag key={`${skill.skill_id}-${skill.title}-${index}`}>
               {skill.title}
-              <button
-                onClick={clearSkill}
+              {/* TODO: 因为后端接口不支持取消选择skill，所以暂时禁用取消选择按钮 */}
+              {/* <button
+                onClick={() => clearSkill(skill.skill_id)}
                 className="hover:bg-muted-foreground/20 ml-1 rounded-full"
                 type="button"
               >
                 <XIcon className="size-3" />
-              </button>
+              </button> */}
             </Tag>
           ))}
         </div>

frontend/src/hooks/use-iframe-skill.ts

@@ -60,7 +60,7 @@ interface UseIframeSkillReturn {
     title: string;
   }) => Promise<boolean>;
   openSkillDialog: () => void;
-  clearSkill: () => void;
+  clearSkill: (skillId?: string) => void;
 }
 
 interface UseIframeSkillOptions {
@@ -149,12 +149,18 @@ export function useIframeSkill(
 
   // 4. 选择变化时同步到 localStorage
   useEffect(() => {
+    const threadKey = getThreadStorageKey(threadId);
     if (selectedSkills.length === 0) {
+      // 空数组也要同步到存储，避免 UI 状态与缓存不一致
+      window.localStorage.removeItem(STORAGE_KEYS.latest);
+      if (threadKey) {
+        window.localStorage.removeItem(threadKey);
+      }
       return;
     }
+
     const payload = JSON.stringify(selectedSkills);
     window.localStorage.setItem(STORAGE_KEYS.latest, payload);
-    const threadKey = getThreadStorageKey(threadId);
     if (threadKey) {
       window.localStorage.setItem(threadKey, payload);
     }
@@ -262,19 +268,58 @@ export function useIframeSkill(
   }, []);
 
   // 清除选中并发送空 selectedSkills 数组给主页
-  const clearSkill = useCallback(() => {
-    setSelectedSkill(null);
-    setSelectedSkills([]);
-    window.localStorage.removeItem(STORAGE_KEYS.latest);
-    const threadKey = getThreadStorageKey(threadId);
-    if (threadKey) {
-      window.localStorage.removeItem(threadKey);
-    }
-    // 发送空数组给主页，通知取消选择
-    const message = { type: POST_MESSAGE_TYPES.SELECT_SKILLS, selectedSkills: [] };
-    console.log("[useIframeSkill] clearSkill, sending selectedSkills=[]:", message);
-    sendToParent(message);
-  }, [threadId]);
+  const clearSkill = useCallback(
+    (skillId?: string) => {
+      const removeAll = !skillId;
+      const nextSelectedSkills = removeAll
+        ? []
+        : selectedSkills.filter((skill) => skill.skill_id !== String(skillId));
+
+      setSelectedSkills(nextSelectedSkills);
+      setSelectedSkill(nextSelectedSkills[0] ?? null);
+
+      // 同步 latest 缓存：仅删除对应 skill（或全部清空）
+      const latestSkills = parseStoredSkills(
+        window.localStorage.getItem(STORAGE_KEYS.latest),
+      );
+      const nextLatestSkills = removeAll
+        ? []
+        : latestSkills.filter((skill) => skill.skill_id !== String(skillId));
+      if (nextLatestSkills.length > 0) {
+        window.localStorage.setItem(
+          STORAGE_KEYS.latest,
+          JSON.stringify(nextLatestSkills),
+        );
+      } else {
+        window.localStorage.removeItem(STORAGE_KEYS.latest);
+      }
+
+      // 同步线程缓存：保存剩余数组，空则删除 key
+      const threadKey = getThreadStorageKey(threadId);
+      if (threadKey) {
+        if (nextSelectedSkills.length > 0) {
+          window.localStorage.setItem(
+            threadKey,
+            JSON.stringify(nextSelectedSkills),
+          );
+        } else {
+          window.localStorage.removeItem(threadKey);
+        }
+      }
+
+      // 通知宿主页当前剩余技能
+      const message = {
+        type: POST_MESSAGE_TYPES.SELECT_SKILLS,
+        selectedSkills: nextSelectedSkills.map((skill) => ({
+          id: skill.skill_id,
+          name: skill.title,
+        })),
+      } as const;
+      console.log("[useIframeSkill] clearSkill:", message);
+      sendToParent(message);
+    },
+    [selectedSkills, threadId],
+  );
 
   return {
     selectedSkill,