ci: 修复 xwin 编译 - 添加 Windows MSVC 目标

问题：
- xwin 编译时需要 x86_64-pc-windows-msvc 目标
- 错误：can't find crate for std

修复：
- 在安装 xwin 前添加 rustup target add x86_64-pc-windows-msvc
- 使用官方 xwin crate（非 git 版本）
- 添加 xwin download 步骤下载预编译 CRT

.gitea/workflows/build.yml

@@ -15,36 +15,32 @@ jobs:
       run: |
         curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y --profile minimal
         source $HOME/.cargo/env
+        # 添加 Windows MSVC 目标（xwin 需要）
+        rustup target add x86_64-pc-windows-msvc
         
     - name: Install xwin (MinGW CRT)
       run: |
         source $HOME/.cargo/env
-        cargo install --git https://github.com/Jake-Shadle/xwin.git xwin --target x86_64-pc-windows-msvc
+        # 安装 xwin（需要 x86_64-pc-windows-msvc 目标）
+        cargo install xwin
         
-    - name: Download MinGW-w64 compiler
+    - name: Download MinGW CRT
       run: |
-        mkdir -p $HOME/mingw
-        cd $HOME/mingw
-        
-        # 下载预编译的 MinGW-w64
-        curl -L -O x86_64-12.0.0-release-posix-seh-rt_v8-rev0.7z \
-          https://github.com/niXman/mingw-builds-binaries/releases/download/12.0.0-rt_v8-rev0/x86_64-12.0.0-release-posix-seh-rt_v8-rev0.7z
-        
-        # 解压
-        7z x x86_64-12.0.0-release-posix-seh-rt_v8-rev0.7z -y
-        
-        # 设置环境变量
-        echo "MINGW_HOME=$HOME/mingw/mingw64" >> $GITHUB_ENV
-        echo "PATH=$HOME/mingw/mingw64/bin:$PATH" >> $GITHUB_ENV
+        source $HOME/.cargo/env
+        # 下载预编译的 MinGW CRT
+        xwin download --accept-license
         
     - name: Build
       run: |
         source $HOME/.cargo/env
-        source $GITHUB_ENV
         
-        export CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_LINKER=x86_64-w64-mingw32-gcc
-        export CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_AR=ar
-        export CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_RANLIB=ranlib
+        # 设置 xwin 环境变量
+        export CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_LINKER=xwin-link
+        export CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_AR=xwin-lib
+        export CARGO_TARGET_X86_64_PC_WINDOWS_MSVC_RANLIB=true
+        
+        # 使用 xwin 提供的 SDK
+        export XWIN_PATH=$HOME/.cache/xwin
         
         cargo build --release --target x86_64-pc-windows-msvc
         
@@ -55,7 +51,7 @@ jobs:
         cd dist
         echo "ReadFlow for Windows" > README.txt
         echo "Version: ${GITEA_REF_NAME}" >> README.txt
-        echo "Built with: MinGW-w64 (precompiled)" >> README.txt
+        echo "Built with: xwin + MSVC" >> README.txt
         echo "Date: $(date)" >> README.txt
         zip -r readflow-windows-x86_64.zip readflow.exe README.txt
         
@@ -76,7 +72,7 @@ jobs:
           RELEASE_ID=$(curl -s -X POST "${URL}/api/v1/repos/${REPO}/releases" \
             -H "Authorization: token ${TOKEN}" \
             -H "Content-Type: application/json" \
-            -d "{\"tag_name\": \"${TAG}\", \"name\": \"ReadFlow ${TAG}\", \"body\": \"Release ${TAG}\\n\\nBuilt with MinGW-w64 (预编译) + xwin\", \"draft\": false}" \
+            -d "{\"tag_name\": \"${TAG}\", \"name\": \"ReadFlow ${TAG}\", \"body\": \"Release ${TAG}\\n\\nBuilt with xwin (预编译 MinGW CRT)\", \"draft\": false}" \
             | jq -r '.id')
         fi