fix: keep agent status with replies

frontend/src/components/agent-activity-status.tsx

@@ -1,3 +1,4 @@
+import { CircleCheck } from "lucide-react";
 import { ThinkingOrb, type OrbState } from "thinking-orbs";
 
 const labels = {
@@ -7,18 +8,23 @@ const labels = {
   listening: "正在聆听…",
   composing: "正在组织回答…",
   shaping: "正在生成结果…",
-} as const satisfies Record<OrbState, string>;
+  completed: "回答已完成",
+} as const satisfies Record<OrbState | "completed", string>;
+
+export type AgentActivityState = OrbState | "completed";
 
 export function AgentActivityStatus({
   state,
   label = labels[state],
 }: Readonly<{
-  state: OrbState;
+  state: AgentActivityState;
   label?: string;
 }>) {
   return (
-    <div className="agent-activity-status" role="status">
-      <ThinkingOrb aria-hidden="true" state={state} size={20} />
+    <div className="agent-activity-status" role={state === "completed" ? undefined : "status"}>
+      {state === "completed"
+        ? <CircleCheck aria-hidden="true" size={20} strokeWidth={1.8} />
+        : <ThinkingOrb aria-hidden="true" state={state} size={20} />}
       <span>{label}</span>
     </div>
   );

frontend/src/components/chat-message-row.tsx

@@ -50,12 +50,17 @@ export function ChatMessageRow({ message }: { readonly message: ChatMessageView
       <div className="message-content">
         <div className="message-bubble">
           {message.role === "assistant" ? (
-            message.state === "thinking"
-              ? <AgentActivityStatus state="working" label="正在核对星盘信息…" />
-              : <>
-                {message.state === "streaming" && <AgentActivityStatus state="composing" />}
-                <ChatMessageContent text={message.text} />
-              </>
+            <>
+              <AgentActivityStatus
+                state={message.state === "thinking"
+                  ? "working"
+                  : message.state === "streaming"
+                    ? "composing"
+                    : "completed"}
+                label={message.state === "thinking" ? "正在核对星盘信息…" : undefined}
+              />
+              {message.text && <ChatMessageContent text={message.text} />}
+            </>
           ) : <p>{message.text}</p>}
         </div>
       </div>