Fix pytest-randomly seed overflow in numpy legacy API

[I-am-Uchenna]

Closes #725

Problem

When pytest-randomly (older versions) generates seeds that exceed 2**32 - 1, numpy.random.seed() raises a ValueError because its legacy API only accepts seeds in the range [0, 2**32 - 1].

ValueError: Seed must be between 0 and 2**32 - 1

This surfaces as random, hard-to-reproduce test failures depending on the seed pytest-randomly picks.

Fix

Adds a tests/conftest.py that monkey-patches numpy.random.seed at module load time to constrain any integer seed via seed % (2**32). Non-integer and None seeds pass through unchanged.

The patch is minimal and project-scoped - it only affects the test suite, not library code.

Tests

Adds tests/test_conftest.py with 7 tests covering:

• Seeds exceeding uint32 max
• • Seed at the uint32 boundary (2**32)
• • Seed zero
• • Seed at max valid value (2**32 - 1)
• • Seed None (random)
• • Determinism preserved after patching
• • Large seed determinism (consistent wrapping)
    All tests pass. Both files are Black-formatted.

Reproduction

pip install pytest-randomly==1.2.3
pytest tests/ -p randomly --randomly-seed=5765063658
# ValueError: Seed must be between 0 and 2**32 - 1

# With the fix applied:
pytest tests/ -p randomly --randomly-seed=5765063658
# All tests pass