feat: 重构数据存储路径并优化任务通知机制

将审计日志、会话数据和定时任务文件移动到统一的data目录下
为后台任务添加完成回调功能，优化CC任务完成后的通知流程
更新README和ROADMAP文档，标记已完成的功能项

orchestrator/agent.py

@@ -51,6 +51,10 @@ Your responsibilities:
 6. WEB / SEARCH: Use the `web` tool when the user needs current information. \
    Call it ONCE (or at most twice with a refined query). Then synthesize and reply — \
    do NOT keep searching in a loop. If the first search returns results, use them.
+7. BACKGROUND TASKS: When `create_conversation` or `send_to_conversation` returns a \
+   "Task #... started" message, the task is running in the background. \
+   Immediately reply to the user that the task has started and they will be notified. \
+   Do NOT call `task_status` in a loop waiting for it — the system sends a notification when done.
 
 Guidelines:
 - Relay Claude Code's output verbatim.
@@ -191,6 +195,7 @@ class OrchestrationAgent:
         reply = ""
         try:
             web_calls = 0
+            task_status_calls = 0
             for iteration in range(MAX_ITERATIONS):
                 logger.debug("    LLM call #%d", iteration)
                 ai_msg: AIMessage = await self._llm_with_tools.ainvoke(messages)
@@ -221,6 +226,16 @@ class OrchestrationAgent:
                             )
                             continue
 
+                    if tool_name == "task_status":
+                        task_status_calls += 1
+                        if task_status_calls > 1:
+                            result = "Task is still running in the background. Stop polling and tell the user they will be notified when it completes."
+                            logger.warning("    task_status poll limit exceeded, blocking")
+                            messages.append(
+                                ToolMessage(content=str(result), tool_call_id=tool_id)
+                            )
+                            continue
+
                     tool_obj = _TOOL_MAP.get(tool_name)
                     if tool_obj is None:
                         result = f"Unknown tool: {tool_name}"