update: readme, template

.github/workflows/docker.yaml

@@ -37,7 +37,7 @@ jobs:
             ${{ secrets.DOCKER_HUB_USERNAME }}/sub2sing-box
             ghcr.io/${{ github.repository }}
 
-      - name: Prepare tags and build args
+      - name: Prepare args
         id: prep
         run: |
           if [[ "${{ github.event_name }}" == 'workflow_dispatch' ]]; then
@@ -49,7 +49,7 @@ jobs:
           if [[ "$GITHUB_REF" == 'refs/tags/'* ]]; then
             VERSION=$TAG_NAME
           fi
-          echo "version=${VERSION}" >> $GITHUB_ENV
+          echo "version=$VERSION" >> $GITHUB_ENV
 
       - name: Set up Docker buildx
         uses: docker/setup-buildx-action@v3
@@ -59,7 +59,7 @@ jobs:
         with:
           context: .
           file: ./Dockerfile
-          build-args: version=${{ steps.prep.outputs.version }}
+          build-args: version=${{ env.version }}
           push: true
           platforms: linux/amd64,linux/arm,linux/arm64
           tags: ${{ steps.meta.outputs.tags }}