fix(scripts): 修复 Windows 启动脚本兼容性和稳定性问题

- start.bat: 移除后端日志文件重定向，避免文件锁定导致启动失败

- start.bat: 用 ping 替代 timeout，修复 PowerShell 下错误

- start.bat: 健康检查改为 health 接口，提升可靠性

- start.bat: 修复前端 cd 路径带空格时的引号嵌套问题，使用 /B 在当前窗口后台运行

- stop.bat: 同样用 ping 替代 timeout 提升兼容性

script/start.bat

@@ -11,11 +11,11 @@ REM 1. Clean processes on ports
 echo [1/4] Cleaning old processes...
 for /f "tokens=5" %%a in ('netstat -ano ^| findstr ":%BACKEND_PORT%" ^| findstr "LISTENING"') do (
     taskkill /F /PID %%a >nul 2>&1
-    echo   Stopped port %BACKEND_PORT% (PID: %%a)
+    echo   Stopped backend (PID: %%a)
 )
 for /f "tokens=5" %%a in ('netstat -ano ^| findstr ":%FRONTEND_PORT%" ^| findstr "LISTENING"') do (
     taskkill /F /PID %%a >nul 2>&1
-    echo   Stopped port %FRONTEND_PORT% (PID: %%a)
+    echo   Stopped frontend (PID: %%a)
 )
 echo   Cleanup complete!
 echo.
@@ -33,12 +33,11 @@ if exist "%ROOT_PATH%\venv\Scripts\python.exe" (
 cd /d "%ROOT_PATH%"
 set "PYTHONIOENCODING=utf-8"
 
-REM Clear old logs
+REM Ensure logs directory exists (used by application logger)
-if exist "%ROOT_PATH%\logs\backend_startup.log" del /f "%ROOT_PATH%\logs\backend_startup.log" >nul 2>&1
+mkdir "%ROOT_PATH%\logs" 2>nul
-if exist "%ROOT_PATH%\logs\backend_error.log" del /f "%ROOT_PATH%\logs\backend_error.log" >nul 2>&1
 
-REM Start backend
+REM Start backend in background of current console
-start /B "" "%PYTHON_PATH%" -u main.py >"%ROOT_PATH%\logs\backend_startup.log" 2>"%ROOT_PATH%\logs\backend_error.log"
+start /B "" "%PYTHON_PATH%" -u main.py
 echo   Backend started
 echo.
 
@@ -48,33 +47,25 @@ set RETRY_COUNT=0
 set BACKEND_READY=0
 
 :WAIT_LOOP
-if %RETRY_COUNT% geq 10 goto WAIT_DONE
+if %RETRY_COUNT% geq 15 goto WAIT_DONE
-timeout /t 2 /nobreak >nul
+REM Use ping instead of timeout for PowerShell compatibility
+ping -n 3 127.0.0.1 >nul 2>&1
 set /a RETRY_COUNT+=1
 
-ping -n 1 127.0.0.1 -w 500 >nul
+REM Try to connect to backend health endpoint
-timeout /t 1 /nobreak >nul
+powershell -Command "try { $r = Invoke-RestMethod -Uri 'http://127.0.0.1:9949/health' -TimeoutSec 2 -ErrorAction Stop; exit 0 } catch { exit 1 }" >nul 2>&1
-
-REM Try to connect to backend
-powershell -Command "try { $r = Invoke-RestMethod -Uri 'http://127.0.0.1:9949/' -TimeoutSec 2 -ErrorAction Stop; exit 0 } catch { exit 1 }" >nul 2>&1
 if %errorlevel% equ 0 (
     set BACKEND_READY=1
     goto WAIT_DONE
 )
-echo   Waiting... (%RETRY_COUNT%/10)
+echo   Waiting... (%RETRY_COUNT%/15)
-
-if exist "%ROOT_PATH%\logs\backend_startup.log" (
-    for /f "delims=" %%i in ('powershell -Command "Get-Content '%ROOT_PATH%\logs\backend_startup.log' -Tail 1" 2^>nul') do (
-        echo     Log: %%i
-    )
-)
 goto WAIT_LOOP
 
 :WAIT_DONE
 if %BACKEND_READY% equ 0 (
     echo.
-    echo Backend failed to start!
+    echo Backend failed to start within 30 seconds!
-    echo Check error log: %ROOT_PATH%\logs\backend_error.log
+    echo Check the console output above for errors.
     pause
     exit /b 1
 )
@@ -83,7 +74,9 @@ echo.
 
 REM 4. Start Frontend
 echo [4/4] Starting frontend (Vite)...
-start /B "" cmd /c "cd /d "%ROOT_PATH%\frontend" && npm run dev" >nul 2>&1
+cd /d "%ROOT_PATH%\frontend"
+start /B "" cmd /c "npm run dev"
+cd /d "%ROOT_PATH%"
 echo   Frontend started
 echo.
 
@@ -91,5 +84,5 @@ echo === All services started ===
 echo Backend: http://127.0.0.1:9949
 echo Frontend: http://localhost:9948
 echo.
-echo Please open frontend in browser
+echo Press any key to close this window (services will keep running).
-timeout /t 5 >nul
+pause >nul

script/stop.bat

@@ -31,7 +31,8 @@ echo   Stopped %STOPPED_COUNT% process(es)
 echo.
 
 echo [2/2] Waiting for processes to fully stop...
-timeout /t 2 /nobreak >nul
+REM Use ping instead of timeout for PowerShell compatibility
+ping -n 3 127.0.0.1 >nul 2>&1
 
 echo.
 echo === Done ===