tests: Migrate from unmaintained pytest-lazy-fixture to pytest-lazy-fixtures

[matthewelwell]

Background

api/pyproject.toml currently depends on pytest-lazy-fixture==0.6.3, which has been unmaintained since 2020. It accesses pytest's internal CallSpec2.funcargs attribute, which was removed in pytest 9, so the package is incompatible with pytest 8 and above:

ERROR tests/unit/permissions/permission_service/test_get_permitted_projects_for_user.py - AttributeError: 'CallSpec2' object has no attribute 'funcargs'

This was surfaced while investigating #7756 (removing the [tool.uv].override-dependencies block). For now, pytest is capped at <8 in the dev extra to keep the existing tests green.

Proposed work

Migrate the ~297 lazy_fixture(...) call sites in api/tests/ to the maintained fork pytest-lazy-fixtures (note the plural), which uses a different API:

• lazy_fixture("name") → lf("name")
• New: lfc("name", arg) for fixture composition

Once migrated, the pytest cap can be lifted and we'll be able to take pytest 8/9 updates.

Acceptance criteria

• Replace pytest-lazy-fixture with pytest-lazy-fixtures in api/pyproject.toml
• Update all call sites under api/tests/ to the new API
• Lift the pytest<8 cap in api/pyproject.toml
• Remove the TODO markers added in chore(api): Remove uv override-dependencies block #7756 referencing this issue