feat(h5): web 联网能力、实时查询路由与 session Finish 对齐

- 新增 web 能力并挂载 platform/web（web_search/fetch_url）
- 实时查询强制 web skill，router fallback 与 await session Finish
- Session Broker 覆盖率/指标、stream replay 与相关单测/E2E 脚本

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

src/components/MessageList.tsx

@@ -144,6 +144,31 @@ function isToolOnlyAssistantMessage(message: Message) {
   );
 }
 
+function TypingBubble() {
+  return (
+    <div className="msg-bubble msg-bubble-assistant msg-typing">
+      <span className="typing-dots">
+        <span />
+        <span />
+        <span />
+      </span>
+    </div>
+  );
+}
+
+function shouldShowEndTypingIndicator(messages: Message[], streaming: boolean) {
+  if (!streaming) return false;
+  const lastUserIndex = messages.findLastIndex((message) => message.role === 'user');
+  if (lastUserIndex < 0) return true;
+  const assistantReply = messages
+    .slice(lastUserIndex + 1)
+    .find((message) => message.role === 'assistant');
+  if (!assistantReply) return true;
+  if (getDisplayText(assistantReply).trim() || getThinking(assistantReply)) return false;
+  if (hasToolActivity(assistantReply)) return false;
+  return true;
+}
+
 function ToolBadge({ message, active }: { message: Message; active: boolean }) {
   if (message.role !== 'assistant') return null;
   const tools = message.content.filter((c) => c.type === 'toolRequest' || c.type === 'toolResponse');
@@ -265,6 +290,7 @@ function MessageRow({
   sessionId,
   compact = false,
   activeToolMessage = false,
+  showInlineTyping = false,
 }: {
   message: Message;
   avatarUrl: string | null;
@@ -279,6 +305,7 @@ function MessageRow({
   sessionId?: string;
   compact?: boolean;
   activeToolMessage?: boolean;
+  showInlineTyping?: boolean;
 }) {
   const [actionsOpen, setActionsOpen] = useState(false);
   const rawText = getDisplayText(message);
@@ -295,7 +322,11 @@ function MessageRow({
       <div className={`msg-row msg-row-assistant`}>
         <TKMindAvatar />
         <div className="msg-content">
-          <ToolBadge message={message} active={activeToolMessage} />
+          {showInlineTyping ? (
+            <TypingBubble />
+          ) : (
+            <ToolBadge message={message} active={activeToolMessage} />
+          )}
         </div>
       </div>
     );
@@ -471,6 +502,20 @@ export function MessageList({
   const visibleMessages = renderableMessages.filter(
     (message) => !isToolOnlyAssistantMessage(message) || message === activeToolMessage,
   );
+  const showEndTyping = shouldShowEndTypingIndicator(renderableMessages, streaming);
+  const lastUserIndex = renderableMessages.findLastIndex((message) => message.role === 'user');
+  const inlineTypingMessage =
+    lastUserIndex >= 0
+      ? renderableMessages
+          .slice(lastUserIndex + 1)
+          .find(
+            (message) =>
+              message.role === 'assistant' &&
+              !getDisplayText(message).trim() &&
+              !getThinking(message) &&
+              !hasToolActivity(message),
+          ) ?? null
+      : null;
 
   return (
     <div className="message-list">
@@ -499,21 +544,16 @@ export function MessageList({
               publishUsername={publishUsername}
               compact={compact}
               activeToolMessage={message === activeToolMessage}
+              showInlineTyping={showEndTyping && message === inlineTypingMessage}
             />
           </div>
         );
       })}
-      {streaming && (
-        <div className="msg-row msg-row-assistant">
+      {showEndTyping && !inlineTypingMessage && (
+        <div className="msg-row msg-row-assistant" role="status" aria-live="polite" aria-label="助手正在回复">
           <TKMindAvatar />
           <div className="msg-content">
-            <div className="msg-bubble msg-bubble-assistant msg-typing">
-              <span className="typing-dots">
-                <span />
-                <span />
-                <span />
-              </span>
-            </div>
+            <TypingBubble />
           </div>
         </div>
       )}