Import project source and Git ignore rules [skip ci]

.github/workflows/lean_action_ci.yml

@@ -0,0 +1,21 @@
+name: Lean Action CI
+
+on:
+  push:
+  pull_request:
+  workflow_dispatch:
+
+# Sets permissions of the GITHUB_TOKEN to allow deployment to GitHub Pages
+permissions:
+  contents: read # Read access to repository contents
+  pages: write # Write access to GitHub Pages
+  id-token: write # Write access to ID tokens
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v5
+      - uses: leanprover/lean-action@v1
+      - uses: leanprover-community/docgen-action@v1