Report non-finite integer values as configuration errors

[Imkkey]

Integer currently raises raw OverflowError for infinity and ValueError for NaN. That also prevents OneOf([int, float]) from reaching its valid Number fallback; NaN is incorrectly reported as a ConfigTemplateError.

Catch those float-to-integer conversion failures and raise ConfigValueError with the configuration key instead. Finite floats and arbitrarily large integers keep their existing behavior.

The tests load YAML .inf, -.inf and .nan and cover direct validation, successful OneOf fallback, and rejection when no candidate accepts the value. A changelog entry is included.

Validation on Python 3.12.14:

• 9 regression cases fail before the fix and pass afterward; 4 finite-number controls also pass
• All 125 template tests and 312 core tests pass
• Full suite after building docs: 313 passed, 1 existing failure in test_bump_version_applies_sequential_changelog_updates. A clean upstream checkout has the same failure (300 passed, 1 failed)
• Ruff lint/format, mypy targeting Python 3.10, strict Sphinx build and changelog checks pass