ci: smoke workflow for the Fly runner

.gitea/workflows/smoke.yml

@@ -0,0 +1,14 @@
+name: smoke
+on:
+  workflow_dispatch:
+  push:
+    paths: [".gitea/workflows/smoke.yml"]
+jobs:
+  smoke:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: |
+          echo "runner ok on $(hostname)"
+          node --version
+          ls