piano-sheet: ns cube-piano-sheet → cube-piano

ns 跟 app 名解耦，workflow 加 NS env 不再 cube-$APP 拼。

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

@@ -17,6 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     env:
       APP: piano-sheet
+      NS: cube-piano
       IMAGE: registry.famzheng.me/mochi/piano-sheet
     steps:
       - uses: actions/checkout@v4
@@ -51,5 +52,5 @@ jobs:
 
       - name: Roll out to k3s
         run: |
-          kubectl -n "cube-$APP" set image "deploy/$APP" "$APP=$IMAGE:${{ steps.tag.outputs.sha }}"
-          kubectl -n "cube-$APP" rollout status "deploy/$APP" --timeout=120s
+          kubectl -n "$NS" set image "deploy/$APP" "$APP=$IMAGE:${{ steps.tag.outputs.sha }}"
+          kubectl -n "$NS" rollout status "deploy/$APP" --timeout=120s