add publish workflow

.forgejo/workflows/publish.yml

@@ -0,0 +1,33 @@
+name: publish-image
+on:
+  push:
+    tags: ['v*']
+
+jobs:
+  docker:
+    runs-on: docker
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: docker/login-action@v3
+        with:
+          registry: git.snakedesert.se
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - uses: docker/metadata-action@v5
+        id: meta
+        with:
+          images: git.snakedesert.se/${{ github.repository }}
+          tags: |
+            type=ref,event=tag
+            type=semver,pattern={{version}}
+            type=raw,value=latest
+
+      - uses: docker/build-push-action@v6
+        with:
+          context: .
+          target: prod
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}