Phase 0 评审二次修复：init.sh 增加 .exe fallback + 文档统一 MSYS2 环境声明

init.ps1

@@ -2,21 +2,30 @@
 
 # 标准启动与验证入口（Windows PowerShell 版），与 init.sh 等价，二选一：
 #   - Windows 原生 PowerShell：用本文件 ./init.ps1
-#   - WSL / Git Bash / macOS / Linux：用 ./init.sh
+#   - MSYS2 / Git Bash / WSL / Linux：用 ./init.sh
 # 一条命令完成：依赖安装 -> 基础验证 -> 打印启动命令。
 
 $ErrorActionPreference = "Stop"
 Set-Location -Path $PSScriptRoot
 
-$InstallCmd = ".venv/bin/pip3.12 install -r requirements.txt"
-$VerifyCmd  = ".venv/bin/python3.12 manage.py check"
-$StartCmd   = ".venv/bin/python3.12 manage.py runserver"
+$PythonPath = ".venv/bin/python3.12"
+$PipPath    = ".venv/bin/pip3.12"
 
-if (-not (Test-Path ".venv/bin/python3.12") -and -not (Test-Path ".venv/bin/python3.12.exe")) {
-  Write-Error "venv 不存在或损坏，请先运行: python3.12 -m venv .venv"
+# MSYS2/MinGW venv 中可执行文件带 .exe 后缀
+if (-not (Test-Path $PythonPath) -and (Test-Path "$PythonPath.exe")) {
+  $PythonPath = "$PythonPath.exe"
+  $PipPath    = "$PipPath.exe"
+}
+
+if (-not (Test-Path $PythonPath)) {
+  Write-Error "venv 不存在或已损坏。请先运行: python3.12 -m venv .venv"
   exit 1
 }
 
+$InstallCmd = "$PipPath install -r requirements.txt"
+$VerifyCmd  = "$PythonPath manage.py check"
+$StartCmd   = "$PythonPath manage.py runserver"
+
 Write-Host "==> 当前目录: $($PWD.Path)"
 
 Write-Host "==> 同步依赖"