ci(piano-sheet): apply k8s manifests before rollout

CI 第一次跑时 ns / PVC / svc / ingress 还不存在，直接 set image
会失败。加一步 kubectl apply -f apps/piano-sheet/k8s/，让 ns +
PVC + deployment + service + ingress + middleware 都先就位，再
做镜像 set + rollout status。

.gitea/workflows/deploy-piano-sheet.yml

@@ -45,6 +45,10 @@ jobs:
           docker build -f "apps/$APP/Dockerfile" -t "$IMAGE:${{ steps.tag.outputs.sha }}" .
           docker push "$IMAGE:${{ steps.tag.outputs.sha }}"
 
+      - name: Initialize K8s resources
+        run: |
+          kubectl apply -f apps/piano-sheet/k8s/
+
       - name: Roll out to k3s
         run: |
           kubectl -n "cube-$APP" set image "deploy/$APP" "$APP=$IMAGE:${{ steps.tag.outputs.sha }}"