chore: initial import 萌邮 MengPost (React+Vite + Go+Gin)

Made-with: Cursor

build.bat

@@ -0,0 +1,16 @@
+@echo off
+rem 构建前端静态产物到 mengpost-frontend\dist
+setlocal
+set ROOT=%~dp0
+cd /d %ROOT%mengpost-frontend
+if not exist node_modules (
+    call npm install || goto :err
+)
+call npm run build || goto :err
+echo.
+echo  前端已构建: %ROOT%mengpost-frontend\dist
+endlocal & exit /b 0
+
+:err
+echo 构建失败
+endlocal & exit /b 1