fix: checkout 后显式 git fetch 切换触发分支，避免始终部署 main 代码；Dockerfile 添加 BuildKit cache mount 加速构建

.gitea/workflows/deploy.yml

@@ -10,12 +10,19 @@ jobs:
     steps:
       - name: Checkout
         uses: "http://8.161.227.145:3000/huanghaosheng/checkout@releases/v4"
-        with:
-          ref: ${{ github.ref }}
 
       - name: Install Docker CLI
         run: apk add --no-cache docker-cli docker-cli-compose rsync
 
+      - name: Switch to trigger branch
+        run: |
+          git config --global --add safe.directory "$(pwd)"
+          echo "触发分支: ${GITHUB_REF_NAME}"
+          git fetch origin "${GITHUB_REF_NAME}" --depth=1
+          git checkout "${GITHUB_REF_NAME}"
+          git reset --hard "origin/${GITHUB_REF_NAME}"
+          echo "当前提交: $(git log -1 --oneline)"
+
       - name: Sync to deploy directory
         run: |
           mkdir -p /root/camtalk