Initial upload with CI/CD workflow

.gitea/workflows/format.yml

@@ -0,0 +1,24 @@
+name: Format
+
+on:
+  push:
+    branches: [main]
+
+jobs:
+  format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+      - name: Install formatters
+        run: |
+          pip install black isort
+      - name: Run black
+        run: |
+          black --check shellgen/ tests/
+      - name: Run isort
+        run: |
+          isort --check-only shellgen/ tests/