Add AssistantIdentity component to AssistantPage for assistant ID display and copy functionality

- Introduce the AssistantIdentity component to show the current assistant ID and provide a copy-to-clipboard feature.
- Update multiple sections of AssistantPage to include the AssistantIdentity component, enhancing user interaction with assistant IDs.
- Ensure the component handles the display of the assistant ID and provides feedback when copied successfully.

frontend/src/components/pages/AssistantPage.tsx

@@ -1146,6 +1146,7 @@ export function AssistantPage() {
               value={difyForm.name}
               onChange={(value) => updateDifyForm("name", value)}
             />
+            <AssistantIdentity assistantId={editingId} />
           </div>
 
           <div className="flex shrink-0 gap-2">
@@ -1244,6 +1245,7 @@ export function AssistantPage() {
               value={fastGptForm.name}
               onChange={(value) => updateFastGptForm("name", value)}
             />
+            <AssistantIdentity assistantId={editingId} />
           </div>
 
           <div className="flex shrink-0 gap-2">
@@ -1348,6 +1350,7 @@ export function AssistantPage() {
               value={openCodeForm.name}
               onChange={(value) => updateOpenCodeForm("name", value)}
             />
+            <AssistantIdentity assistantId={editingId} />
           </div>
 
           <div className="flex shrink-0 gap-2">
@@ -1465,6 +1468,7 @@ export function AssistantPage() {
             value={form.name}
             onChange={(value) => updateForm("name", value)}
           />
+          <AssistantIdentity assistantId={editingId} />
         </div>
 
         <div className="flex shrink-0 gap-2">
@@ -1879,6 +1883,37 @@ function EditorBackButton({ onClick }: { onClick: () => void }) {
   );
 }
 
+function AssistantIdentity({ assistantId }: { assistantId: string | null }) {
+  const [copied, setCopied] = useState(false);
+
+  async function copyId() {
+    if (!assistantId) return;
+    await navigator.clipboard.writeText(assistantId);
+    setCopied(true);
+    window.setTimeout(() => setCopied(false), 1600);
+  }
+
+  return (
+    <div className="ml-1 flex shrink-0 items-center rounded-full border border-hairline bg-canvas-soft pl-2.5 text-[11px] text-muted-foreground">
+      <span className="font-mono">
+        {assistantId ? `ID · ${assistantId}` : "ID · 保存后生成"}
+      </span>
+      {assistantId && (
+        <button
+          type="button"
+          onClick={() => void copyId()}
+          className="ml-1 flex h-7 w-7 items-center justify-center rounded-full text-muted-soft transition-colors hover:bg-surface-strong hover:text-foreground"
+          aria-label={copied ? "助手 ID 已复制" : "复制助手 ID"}
+          title={copied ? "已复制" : "复制 ID"}
+        >
+          {copied ? <Check size={13} /> : <Copy size={13} />}
+        </button>
+      )}
+      {!assistantId && <span className="h-7 w-2" aria-hidden />}
+    </div>
+  );
+}
+
 function EditableTitle({
   value,
   onChange,