Restore .gitea workflows at repository root

.gitea/workflows/ci.yml

@@ -0,0 +1,20 @@
+name: cloudron-packages-ci
+
+on:
+  workflow_dispatch:
+
+jobs:
+  lint-and-status:
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout repository
+        uses: https://gitea.com/actions/checkout@v4
+
+      - name: Build devtools image if needed
+        run: ./output/run/dev.sh python --version
+
+      - name: Lint repository (strict mode)
+        run: ./output/run/dev.sh python output/scripts/lint_repo.py --strict
+
+      - name: Regenerate status dashboard
+        run: ./output/run/dev.sh python output/scripts/generate_status.py --preserve-timestamp