perf: 优化 Agent 流式会话处理

- 合并流式通知与持久化写入，限制浏览器会话缓存

- 增量投影轮次事件并稳定关联异步工具任务

easyflow-ui-admin/app/src/views/ai/agents/composables/useAgentTryoutRawRounds.test.ts

@@ -241,4 +241,158 @@ describe('useAgentTryoutRawRounds', () => {
       toolCallId: 'call-approval',
     });
   });
+
+  it('异步工作流轮询事件始终归并到首张审批卡', () => {
+    const store = useAgentTryoutRawRounds({
+      mode: 'draft',
+      sessionId: 'session-raw-async-tool',
+    });
+    const roundId = store.createRound('生成文档');
+    store.recordEvent(roundId, {
+      domain: 'TOOL',
+      payload: {
+        input: { user_input: '写一篇小作文' },
+        requestId: 'req-async',
+        resumeToken: 'resume-async',
+        toolCallId: 'submit-call-1',
+        toolName: '文档生成',
+      },
+      type: 'FORM_REQUEST',
+    });
+    store.recordEvent(roundId, {
+      domain: 'TOOL',
+      payload: {
+        asyncTool: true,
+        phase: 'submit',
+        sourceToolCallId: 'submit-call-1',
+        status: 'RUNNING',
+        taskId: 'task-1',
+        toolCallId: 'task-1',
+        toolName: '文档生成',
+      },
+      type: 'TOOL_RESULT',
+    });
+    for (const sourceToolCallId of ['observe-call-1', 'observe-call-2']) {
+      store.recordEvent(roundId, {
+        domain: 'TOOL',
+        payload: {
+          asyncTool: true,
+          input: { taskId: 'task-1' },
+          phase: 'observe',
+          sourceToolCallId,
+          status: 'RUNNING',
+          taskId: 'task-1',
+          toolCallId: 'task-1',
+          toolName: '文档生成',
+        },
+        type: 'TOOL_CALL',
+      });
+    }
+    store.recordEvent(roundId, {
+      domain: 'TOOL',
+      payload: {
+        asyncTool: true,
+        phase: 'result',
+        sourceToolCallId: 'result-call-1',
+        status: 'SUCCEEDED',
+        taskId: 'task-1',
+        toolCallId: 'task-1',
+        toolName: '文档生成',
+      },
+      type: 'TOOL_RESULT',
+    });
+
+    const tools = store
+      .buildTimelineItems()
+      .filter((item) => item.type === 'tool');
+
+    expect(tools).toHaveLength(1);
+    expect(tools[0]).toMatchObject({
+      mode: 'approval',
+      status: 'success',
+      taskId: 'task-1',
+      toolCallId: 'task-1',
+      toolName: '文档生成',
+    });
+  });
+
+  it('连续文本增量压缩后刷新内容保持一致', () => {
+    const sessionId = 'stream-compaction';
+    const store = useAgentTryoutRawRounds({
+      mode: 'draft',
+      sessionId,
+    });
+    const roundId = store.createRound('你好');
+    const liveItems = store.buildTimelineItems();
+    const assistantText = (
+      items: ReturnType<typeof store.buildTimelineItems>,
+    ) =>
+      items
+        .flatMap((item) =>
+          item.type === 'message' && item.role === 'assistant'
+            ? item.parts
+                .filter((part) => part.type === 'text')
+                .map((part) => part.content)
+            : [],
+        )
+        .join('');
+
+    for (const delta of ['你', '好', '，', '世界']) {
+      const event = store.recordEvent(roundId, {
+        domain: 'LLM',
+        payload: { delta },
+        type: 'MESSAGE',
+      });
+      if (!event) {
+        throw new Error('流式事件记录失败');
+      }
+      store.projectEvent(liveItems, roundId, event);
+    }
+
+    expect(store.currentVariant(roundId)?.runtimeEvents).toHaveLength(1);
+    expect(store.currentVariant(roundId)?.runtimeEvents[0]?.payload.delta).toBe(
+      '你好，世界',
+    );
+    expect(assistantText(liveItems)).toBe('你好，世界');
+
+    store.flush();
+    const restored = useAgentTryoutRawRounds({
+      mode: 'draft',
+      sessionId,
+    });
+    expect(assistantText(restored.buildTimelineItems())).toBe('你好，世界');
+  });
+
+  it('存在待持久化增量时结束事件仍立即落盘', () => {
+    const sessionId = 'terminal-persist';
+    const store = useAgentTryoutRawRounds({
+      mode: 'draft',
+      sessionId,
+    });
+    const roundId = store.createRound('结束测试');
+
+    store.recordEvent(roundId, {
+      domain: 'LLM',
+      payload: { reasoning: '思考中' },
+      type: 'THINKING',
+    });
+    store.recordEvent(roundId, {
+      domain: 'SYSTEM',
+      payload: {},
+      type: 'DONE',
+    });
+
+    const restored = useAgentTryoutRawRounds({
+      mode: 'draft',
+      sessionId,
+    });
+    expect(restored.currentVariant(roundId)?.status).toBe('completed');
+    expect(
+      restored
+        .currentVariant(roundId)
+        ?.runtimeEvents.some(
+          (event) => event.domain === 'SYSTEM' && event.type === 'DONE',
+        ),
+    ).toBe(true);
+  });
 });