Switch Gitea workflow back to ubuntu-latest runner; v2.0.49

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

.gitea/workflows/docker-publish.yml

@@ -12,11 +12,14 @@ permissions:
 
 jobs:
   build:
-    runs-on: fast-builder
+    runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4
 
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
@@ -53,7 +56,7 @@ jobs:
         with:
           context: .
           push: true
-          platforms: linux/arm64
+          platforms: linux/amd64,linux/arm64
           tags: ${{ steps.meta.outputs.tags }}
           labels: ${{ steps.meta.outputs.labels }}
           build-args: |