feat(CI): 添加Flutter安装脚本并改进Windows构建流程

添加install_flutter_simple.bat脚本用于在Windows上自动安装Flutter
改进docker.yml中的Windows构建步骤，增加Flutter路径检测和powershell支持

.gitea/workflows/docker.yml

@@ -189,19 +189,51 @@ jobs:
         }
 
     - name: Enable Windows desktop
-      run: flutter config --enable-windows-desktop
+      shell: powershell
+      run: |
+        $flutterPath = Get-Command flutter -ErrorAction SilentlyContinue
+        if (-not $flutterPath) {
+          Write-Host "Flutter not found, checking common locations..."
+          $commonPaths = @(
+            "C:\flutter\bin\flutter.exe",
+            "C:\tools\flutter\bin\flutter.exe",
+            "${env:USERPROFILE}\flutter\bin\flutter.exe"
+          )
+          $flutterFound = $false
+          foreach ($path in $commonPaths) {
+            if (Test-Path $path) {
+              Write-Host "Found Flutter at: $path"
+              $env:PATH = "$(Split-Path $path);$env:PATH"
+              $flutterFound = $true
+              break
+            }
+          }
+          if (-not $flutterFound) {
+            Write-Host "ERROR: Flutter not found. Please install Flutter first."
+            exit 1
+          }
+        }
+        flutter config --enable-windows-desktop
 
     - name: Get dependencies
-      run: flutter pub get
+      shell: powershell  
+      run: |
+        flutter pub get
 
     - name: Generate code
-      run: dart run build_runner build --delete-conflicting-outputs
+      shell: powershell
+      run: |
+        dart run build_runner build --delete-conflicting-outputs
 
     - name: Build Windows Debug
-      run: flutter build windows
+      shell: powershell
+      run: |
+        flutter build windows
 
     - name: Build Windows Release
-      run: flutter build windows --release
+      shell: powershell
+      run: |
+        flutter build windows --release
 
     - name: Upload Debug build artifacts
       uses: actions/upload-artifact@v3

install_flutter_simple.bat

@@ -0,0 +1,44 @@
+@echo off
+REM Simple Flutter installer for Windows Gitea Runner
+
+echo Installing Flutter for Windows...
+
+REM Create flutter directory
+mkdir C:\flutter 2>nul
+
+REM Download Flutter stable version
+echo Downloading Flutter...
+powershell -Command "(New-Object Net.WebClient).DownloadFile('https://storage.googleapis.com/flutter_infra_release/releases/stable/windows/flutter_windows_3.24.5-stable.zip', 'C:\flutter.zip')"
+
+if %errorlevel% neq 0 (
+    echo Download failed, trying alternative...
+    powershell -Command "Invoke-WebRequest -Uri 'https://storage.googleapis.com/flutter_infra_release/releases/stable/windows/flutter_windows_3.24.5-stable.zip' -OutFile 'C:\flutter.zip'"
+)
+
+REM Extract Flutter
+echo Extracting Flutter...
+powershell -Command "Expand-Archive -Path 'C:\flutter.zip' -DestinationPath 'C:\' -Force"
+
+REM Set PATH
+echo Setting PATH...
+set PATH=C:\flutter\bin;%PATH%
+setx PATH "C:\flutter\bin;%PATH%"
+
+REM Clean up
+del C:\flutter.zip
+
+REM Verify installation
+echo Verifying Flutter installation...
+C:\flutter\bin\flutter --version
+
+if %errorlevel% equ 0 (
+    echo SUCCESS: Flutter installed successfully
+    echo Running flutter doctor...
+    C:\flutter\bin\flutter doctor
+) else (
+    echo ERROR: Flutter installation failed
+    exit /b 1
+)
+
+echo Flutter installation complete!
+pause