Adopt the scaffolded CI shape: pre-commit for lint, and run the 81 tests

.github/workflows/ci.yml

@@ -0,0 +1,34 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  lint-and-test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-python@v5
+        with:
+          python-version: "3.12"
+
+      - uses: astral-sh/setup-uv@v5
+
+      # retina-custody is a sibling library on no package index, so pip cannot
+      # resolve the `retina-custody>=0.1.0` dependency on its own. The pin stays
+      # generic in pyproject.toml on purpose: Tower-Finder installs these libs
+      # from local submodule paths, and a direct URL there would collide with
+      # "conflicting URLs for package retina-custody".
+      - run: uv pip install --system "retina-custody @ git+https://github.com/offworldlabs/retina-custody@v0.1.0"
+
+      # Pinned deliberately: an unpinned linter picks up new rules on release
+      # and turns a green branch red without anything in this repo changing.
+      - run: uv pip install --system -e '.[dev]' pre-commit==4.6.2 vulture==2.14
+
+      - run: pre-commit run --all-files --show-diff-on-failure
+
+      - run: pytest

.pre-commit-config.yaml

@@ -1,10 +1,14 @@
-# The dead-code gate lives in offworldlabs/ops and is pinned here. Do not
-# vendor it back into this repo. See 86cb417ty.
-#
-# ruff is deliberately still a separate CI step rather than a hook; aligning
-# this repo with claude-shared's ci-python.yml is a separate piece of work.
+# ruff and the dead-code gate both run through pre-commit, so `pre-commit run
+# --all-files` locally reproduces CI exactly. See 86cb43xya.
 repos:
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.16.2
+    hooks:
+      - id: ruff
+      - id: ruff-format
+
   - repo: https://github.com/offworldlabs/ops
-    rev: dead-code-v1.0
+    rev: hooks-v1.0
     hooks:
       - id: dead-code
+      - id: ruff-config

pyproject.toml

@@ -26,8 +26,10 @@ retina_simulation = ["*.json", "data/*.geojson"]
 [tool.pytest.ini_options]
 testpaths = ["tests"]
 
-# Shared ruff standard for offworldlabs Python repos.
-# Keep in sync across repos; see offworldlabs/ops for the canonical copy.
+# Shared ruff standard for offworldlabs Python repos. The keys below are checked
+# against offworldlabs/ops:ruff-shared.toml by the `ruff-config` pre-commit hook
+# — edit them there, not here. target-version is deliberately per-repo and
+# tracks this package's requires-python.
 [tool.ruff]
 line-length = 120
 target-version = "py310"