[rennf93]

make test (the compose test service, pytest -v --cov=guard --cov-branch) gave 41 failed on master. It gives 0 failed here.

1. uv.lock is gitignored in this repo (git ls-files uv.lock prints nothing), but the Dockerfile ran uv sync --extra dev --frozen and compose.yml bind-mounted ./uv.lock. On a clean clone the build failed with Unable to find lockfile and, once the file was missing, Docker created a directory called uv.lock on the host and the mount failed with not a directory. I copied the guard-core pattern: uv sync --extra dev without --frozen and no uv.lock mount.
2. The engine's SecurityConfig defaults to enable_redis=True and redis_url=redis://localhost:6379. Tests that build a config without a redis_url therefore connect to localhost:6379 inside the test container, where no Redis listens, and the middleware answers 503. Tests that hardcoded the URL now read REDIS_URL the way the conftest does, and a session fixture in tests/conftest.py points the engine default at REDIS_URL when it is set (it does nothing when REDIS_URL is unset, so the CI service container on localhost still works). Files: tests/test_decorators/test_middleware_integration.py, tests/test_middleware/test_redis_unavailable_response.py, tests/conftest.py.

Verification, the compose test service run as the Makefile runs it, in an own compose project with Redis without a host port (the Makefile target itself runs docker compose down --rmi all -v and docker system prune -f, so I did not run it), master vs this branch:

• Python 3.10: master 446 passed, 41 failed; branch 487 passed, 0 failed.
• Python 3.14: master 446 passed, 41 failed; branch 487 passed, 0 failed.
• Master runs used a locally generated uv.lock, because master does not build without one.
• The example service from compose.yml on this branch: healthy, GET / 200, uid=10001 (Python 3.10).
• hadolint 2.15.1 on the Dockerfile: no output.

Not verified: Python versions other than 3.10 and 3.14, and the CI result (see the checks on this PR).