Testing rule

Tests mirror the source layout: tests/unit/test_<layer>/..., tests/integration/..., tests/e2e/....

Structure: tests/unit/ mirrors src/everos/ package-for-package. Put a test next to where its subject lives in the mirror.
Async: pytest-asyncio is in auto mode — write async def test_* directly, no marker needed.
Markers (default run excludes both — -m "not slow and not live_llm"):
- @pytest.mark.slow — tests ≥ ~10s.
- @pytest.mark.live_llm — needs real LLM/embedder credentials. Keep unit tests fast and credential-free; push anything needing real services behind a marker or into integration/e2e.
Fixtures: shared fixtures live in the nearest conftest.py. The root conftest resets module caches (settings/logging/datetime) per test — rely on that for isolation rather than mutating globals.
Module docstring on each test file stating what contract it pins (see existing tests for the style).
Coverage gate: make cov enforces 80% (--cov-fail-under=80). New code should not drop coverage below the gate.
Run make test (unit) and make integration before pushing; both run in CI.