[Python] Release 0.58.0

Performance

• oneOf and anyOf whose branches each require a property fixed to a distinct string validate only the branch matching the instance's value.
• meta.is_valid and meta.validate check a schema against the bundled drafts without converting it first, about 2x faster on the benchmarked schemas.

Fixed

• Crash on free-threaded Python when another thread resized a list or dict during validation.
• find_unsatisfiable missing a oneOf over $ref branches beside a sibling none of them admits.