feat(ci): add ARMv7 architecture support for Docker builds

Author: Aethersailor

.github/workflows/build-dockerhub.yml

@@ -220,9 +220,53 @@ jobs:
           cache-from: type=gha,scope=subconverter
           cache-to: type=gha,mode=max,scope=subconverter
 
+  build-armv7:
+    runs-on: ubuntu-24.04-arm  # 在 ARM64 Runner 上模拟 ARMv7，效率远高于 x86 模拟
+    needs: prepare
+    if: needs.prepare.outputs.is_release == 'true'
+    outputs:
+      digest: ${{ steps.build_image.outputs.digest }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+        with:
+          token: ${{ secrets.PAT_TOKEN }}
+          fetch-depth: 0
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+        with:
+          platforms: arm  # 仅安装 ARMv7 模拟器
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to Docker Hub
+        if: github.event_name != 'pull_request'
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push final image
+        id: build_image
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          push: ${{ github.event_name != 'pull_request' }}
+          platforms: linux/arm/v7
+          tags: ${{ needs.prepare.outputs.tags }}
+          build-args: |
+            THREADS=2
+            SHA=${{ needs.prepare.outputs.sha_short }}
+            VERSION=${{ needs.prepare.outputs.version }}
+          cache-from: type=gha,scope=subconverter-armv7
+          cache-to: type=gha,mode=max,scope=subconverter-armv7
+
   merge-manifest:
     runs-on: ubuntu-latest
-    needs: [prepare, build-amd64, build-arm64]
+    needs: [prepare, build-amd64, build-arm64, build-armv7]
     if: needs.prepare.outputs.is_release == 'true' && github.event_name != 'pull_request'
     steps:
       - name: Set up Docker Buildx
@@ -243,6 +287,7 @@ jobs:
             docker buildx imagetools create \
               -t "$TAG" \
               "${IMAGE_NAME}@${{ needs.build-amd64.outputs.digest }}" \
-              "${IMAGE_NAME}@${{ needs.build-arm64.outputs.digest }}"
+              "${IMAGE_NAME}@${{ needs.build-arm64.outputs.digest }}" \
+              "${IMAGE_NAME}@${{ needs.build-armv7.outputs.digest }}"
           done