fix(docker): push image on PR builds, fix feature branch tags

- Add PR support: build pushes :latest and :pr-<number> tag
- Fix feature branch tags: replace / with - to produce valid Docker tags

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitea/workflows/docker.yaml

@@ -59,16 +59,23 @@ jobs:
       - name: Docker Release - Dev
         if: startsWith(github.ref, 'refs/heads/develop') || startsWith(github.ref, 'refs/heads/feature/')
         run: |
-          docker image tag "$IMAGE:latest" "$IMAGE:${GITHUB_REF_NAME}"
+          TAG="${GITHUB_REF_NAME//\//-}"
+          docker image tag "$IMAGE:latest" "$IMAGE:${TAG}"
 
       - name: Docker Release - Tagged
         if: startsWith(github.ref, 'refs/tags/')
         run: |
           docker image tag "$IMAGE:latest" "$IMAGE:${GITHUB_REF_NAME}"
 
+      - name: Docker Release - PR
+        if: startsWith(github.ref, 'refs/pull/')
+        run: |
+          PR_NUM=${GITHUB_REF#refs/pull/}
+          PR_NUM=${PR_NUM%/head}
+          docker image tag "$IMAGE:latest" "$IMAGE:pr-${PR_NUM}"
 
       - name: Docker Push
-        if: startsWith(github.ref, 'refs/heads/master') || startsWith(github.ref, 'refs/heads/develop') || startsWith(github.ref, 'refs/heads/feature/') || startsWith(github.ref, 'refs/tags/')
+        if: startsWith(github.ref, 'refs/heads/master') || startsWith(github.ref, 'refs/heads/develop') || startsWith(github.ref, 'refs/heads/feature/') || startsWith(github.ref, 'refs/tags/') || startsWith(github.ref, 'refs/pull/')
         env:
           USERNAME: ${{ secrets.DockerUsername }}
           PASSWORD: ${{ secrets.DockerPassword }}