feat(agent): 聊天提交统一走 POST /agent/runs 异步网关

引入 Agent Run 网关替代直连 /sessions/:id/reply，并在 api_lockdown 白名单中放行新入口，避免策略拦截导致聊天不可用。

Co-authored-by: Cursor <cursoragent@cursor.com>

src/components/ChatPanel.tsx

@@ -134,7 +134,11 @@ export function ChatPanel({
     bottomRef.current?.scrollIntoView({ behavior: 'smooth' });
   }, [messages, chatState, pendingTool]);
 
-  const busy = chatState === 'streaming' || chatState === 'loading' || chatState === 'connecting';
+  const busy =
+    chatState === 'streaming' ||
+    chatState === 'loading' ||
+    chatState === 'connecting' ||
+    chatState === 'waiting';
   const offlineBlocked = !online;
   const publishSkillName = user?.publishSkillName ?? 'static-page-publish';
   const hasPublishSkill = grantedSkills?.includes(publishSkillName) ?? false;
@@ -147,6 +151,8 @@ export function ChatPanel({
     ? '网络断开，恢复连接后可继续输入'
     : chatState === 'connecting'
       ? '正在连接会话…'
+      : chatState === 'waiting'
+        ? '消息已收到，正在连接后台…'
       : compact
         ? '在这里继续和 Agent 对话…'
         : randomPrompt;

src/components/ChatView.tsx

@@ -71,7 +71,11 @@ export function ChatView({
     }
   }, [sidebarOpen, onSidebarOpen]);
 
-  const busy = chatState === 'streaming' || chatState === 'loading' || chatState === 'connecting';
+  const busy =
+    chatState === 'streaming' ||
+    chatState === 'loading' ||
+    chatState === 'connecting' ||
+    chatState === 'waiting';
   const showHomeWelcome = messages.length === 0;
 
   const handleSelectSession = (sessionId: string) => {