Fix headless mode: use sleep loop instead of CLI mode (prevent EOF exit)

- Headless now keeps server alive with asyncio.sleep(1) loop
- CLI mode only for non-headless fallback
- Enables running SenSu as daemon/service

main.py

@@ -333,7 +333,11 @@ class SenSuFramework:
             
             # 特殊终端，添加命令行输入处理
             tui = self.service_manager.get_service("tui")
-            if self.headless or not hasattr(tui, 'tui_app'):
+            if self.headless:
+                while self.is_running:
+                    try: await asyncio.sleep(1)
+                    except asyncio.CancelledError: break
+            elif not hasattr(tui, 'tui_app'):
                 await self._run_cli_mode()
             else:
                 # 原有的TUI模式