Disable pytest-beartype-tests in nested collection runs to fix Python 3.14

[adamtheturtle]

Summary

• The custom CI linter (ci/test_custom_linters.py) calls pytest.main(--collect-only) in a loop. On Python 3.14 this crashed with TypeError: Cannot stringify annotation containing string formatting due to an upstream beartype bug ([Bug] @beartype-decorated callables violate PEP 749-compliant annotationlib.Format.STRING, because this is the world we inhabit 🧔‍♀️ <-- what even *is* this emoji? a blond pacman ghost!? beartype/beartype#637) where the pytest-beartype-tests plugin installs a buggy __annotate_beartype__ closure on test functions, which a subsequent nested collection then trips over via inspect.signature(..., annotation_format=Format.STRING).
• Worked around by passing -p no:pytest_beartype_tests to both nested pytest.main invocations — type-checking adds no value for --collect-only runs anyway.

Test plan

• uv run --python=3.14 --all-extras pytest ci/test_custom_linters.py passes (both linter tests, ~2.5 min)
• CI passes on Python 3.13 and 3.14

🤖 Generated with Claude Code

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Note

Low Risk
Low risk: only adjusts CI linter test invocation flags to work around an upstream pytest plugin crash on Python 3.14, without changing production/runtime logic.

Overview
Updates ci/test_custom_linters.py to disable the pytest-beartype-tests plugin (-p no:pytest_beartype_tests) in both nested pytest.main(--collect-only) runs.

This prevents Python 3.14 nested test collection crashes caused by an upstream beartype/pytest plugin bug, while keeping the linter’s collection-only behavior unchanged.

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