feat(docker): enhance Docker build workflow with commit SHA output and digest verification

- Added output for commit SHA in the Docker build workflow to facilitate tagging.
- Introduced a new verification step to ensure both architectures are present for each required variant before proceeding with the release.
- Updated the finalize_release job to tag the correct commit after successful builds and verifications.

.github/workflows/docker-build.yml

@@ -29,6 +29,7 @@ jobs:
     if: github.ref == format('refs/heads/{0}', github.event.repository.default_branch) || github.event_name == 'workflow_dispatch'
     outputs:
       new_tag: ${{ steps.tag_version.outputs.next_version }}
+      commit_sha: ${{ steps.tag_version.outputs.commit_sha }}
     steps:
       - name: Checkout code
         uses: actions/checkout@v6
@@ -37,6 +38,7 @@ jobs:
           ref: ${{ github.event.inputs.branch }}
           token: ${{ secrets.GITHUB_TOKEN }}
 
+      # Compute-only: tag is pushed by finalize_release after everything succeeds.
       - name: Read app version and calculate next Docker build version
         id: tag_version
         run: |
@@ -64,26 +66,7 @@ jobs:
 
           echo "Calculated next Docker version: $NEXT_VERSION"
           echo "next_version=$NEXT_VERSION" >> $GITHUB_OUTPUT
-
-      - name: Create and Push Tag
-        run: |
-          git config --global user.name 'github-actions[bot]'
-          git config --global user.email 'github-actions[bot]@users.noreply.github.com'
-
-          NEXT_TAG="${{ steps.tag_version.outputs.next_version }}"
-          COMMIT_SHA=$(git rev-parse HEAD)
-          echo "Tagging commit $COMMIT_SHA with $NEXT_TAG"
-
-          git tag -a "$NEXT_TAG" -m "Docker build $NEXT_TAG"
-          echo "Pushing tag $NEXT_TAG to origin"
-          git push origin "$NEXT_TAG"
-
-      - name: Verify Tag Push
-        run: |
-          echo "Checking if tag ${{ steps.tag_version.outputs.next_version }} exists remotely..."
-          sleep 5
-          git ls-remote --tags origin | grep "refs/tags/${{ steps.tag_version.outputs.next_version }}" || (echo "Tag push verification failed!" && exit 1)
-          echo "Tag successfully pushed."
+          echo "commit_sha=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT
 
   build:
     needs: tag_release
@@ -204,10 +187,42 @@ jobs:
           if-no-files-found: error
           retention-days: 1
 
-  create_manifest:
+  # Release gate: require both arches for every variant, else block publishing.
+  # Release-only; skipped on dev so the tolerant create_manifest path is kept.
+  verify_digests:
     runs-on: ubuntu-latest
     needs: [tag_release, build]
-    if: ${{ !cancelled() }}
+    if: ${{ always() && needs.tag_release.result == 'success' && needs.tag_release.outputs.new_tag != '' }}
+    steps:
+      - name: Download all digests
+        uses: actions/download-artifact@v8
+        with:
+          pattern: digests-*
+          path: /tmp/digests
+          merge-multiple: false
+
+      - name: Require both arches for every required variant
+        run: |
+          fail=0
+          check() {
+            c=$(find /tmp/digests -type f -path "*/digests-$1-*/*" 2>/dev/null | wc -l | tr -d ' ')
+            if [ "$c" -lt 2 ]; then
+              echo "::error::$1 has $c/2 arch digests — blocking release"
+              fail=1
+            else
+              echo "OK: $1 ($c/2)"
+            fi
+          }
+          check backend-cpu
+          check backend-cuda
+          check backend-cuda126
+          check web-cpu
+          [ "$fail" -eq 0 ] || exit 1
+
+  create_manifest:
+    runs-on: ubuntu-latest
+    needs: [tag_release, build, verify_digests]
+    if: ${{ !cancelled() && needs.verify_digests.result != 'failure' }}
     permissions:
       packages: write
       contents: read
@@ -316,3 +331,38 @@ jobs:
         run: | 
           echo "Multi-arch manifest created for ${{ matrix.name }}!"
           echo "Tags: $(jq -cr '.tags | join(", ")' <<< "$DOCKER_METADATA_OUTPUT_JSON")"
+
+  # Push the git tag only after build, gate, and manifest publish all succeed.
+  finalize_release:
+    runs-on: ubuntu-latest
+    needs: [tag_release, create_manifest]
+    if: ${{ success() && needs.tag_release.outputs.new_tag != '' }}
+    permissions:
+      contents: write
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+        with:
+          fetch-depth: 0
+          ref: ${{ github.event.inputs.branch }}
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Create and push git tag
+        run: |
+          git config --global user.name 'github-actions[bot]'
+          git config --global user.email 'github-actions[bot]@users.noreply.github.com'
+
+          NEXT_TAG="${{ needs.tag_release.outputs.new_tag }}"
+          COMMIT_SHA="${{ needs.tag_release.outputs.commit_sha }}"
+          echo "Tagging commit $COMMIT_SHA with $NEXT_TAG"
+
+          git tag -a "$NEXT_TAG" "$COMMIT_SHA" -m "Docker build $NEXT_TAG"
+          echo "Pushing tag $NEXT_TAG to origin"
+          git push origin "$NEXT_TAG"
+
+      - name: Verify tag push
+        run: |
+          echo "Checking if tag ${{ needs.tag_release.outputs.new_tag }} exists remotely..."
+          sleep 5
+          git ls-remote --tags origin | grep "refs/tags/${{ needs.tag_release.outputs.new_tag }}" || (echo "Tag push verification failed!" && exit 1)
+          echo "Tag successfully pushed."