ci: build and publish OCI image

.forgejo/workflows/publish.yaml

@@ -52,3 +52,27 @@ jobs:
       - run: uv run pytest test
         env:
           ENVIRONMENT: testing
+
+  build:
+    needs: [ ruff, ty, tests ]
+    if: ${{ always() && needs.ruff.result == 'success' && needs.ty.result == 'success' && needs.tests.result == 'success' }}
+    container:
+      image: ghcr.io/catthehacker/ubuntu:act-latest
+      options: -v /dind/docker.sock:/var/run/docker.sock
+    steps:
+      - name: Checkout the repo
+        uses: actions/checkout@v4
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Login to the registry
+        uses: docker/login-action@v3
+        with:
+          registry: guardianproject.dev
+          username: irl
+          password: ${{ secrets.PACKAGE_TOKEN }}
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          file: Containerfile
+          push: true
+          tags: guardianproject.dev/${{ github.repository }}:${{ github.branch }}