Add ruff lint job to CI

Add a lint job to the tests workflow running ruff check and
ruff format --check on every push and pull request.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: raffaelemancuso

.github/workflows/tests.yml

@@ -6,6 +6,21 @@ on:
   pull_request:
 
 jobs:
+  lint:
+    name: Lint and format
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install uv
+        uses: astral-sh/setup-uv@v5
+
+      - name: Ruff lint
+        run: uv run --extra dev ruff check
+
+      - name: Ruff format
+        run: uv run --extra dev ruff format --check
+
   pytest:
     name: Test suite
     runs-on: ubuntu-latest

CLAUDE.md

@@ -33,7 +33,8 @@ uv run --extra docs --extra pandas --extra polars \
   sphinx-build -b doctest docs/source docs/_build/doctest
 ```
 
-CI runs in two workflows: `.github/workflows/tests.yml` (pytest, with the
+CI runs in two workflows: `.github/workflows/tests.yml` (a `lint` job running
+`ruff check` + `ruff format --check`, and a `pytest` job with the
 pandas/polars/db/web/bibliometrics extras so nothing is skipped) and
 `.github/workflows/docs.yml` (the doctests above).