Implement ParquetFormatModel and update write_file to use the format API

[nssalian]

Continued work on #3100

PR Description

Follow-up to #3119. Implements ParquetFormatWriter and ParquetFormatModel, registers Parquet in the FileFormatFactory, and rewrites write_file to dispatch through the factory using the write.format.default table property. Future formats can be added in a similar way.

Rationale for this change

The write.format.default table property was never read - the write path was hardcoded to Parquet. This PR makes the property functional. Also threads file_format through _to_requested_schema / ArrowProjectionVisitor / _construct_field so field ID metadata keys are correct per format (PARQUET:field_id for Parquet, iceberg.id plus iceberg.required for ORC), preparing the write path for ORC support without changing default behavior.

Are these changes tested?

• tests/io/test_format_writers.py adds parametrized tests modeled after Java's BaseFormatModelTests covering round-trip, statistics, null handling, context manager caching, close idempotency, close-without-write, and ORC vs Parquet field ID dispatch.
• tests/io/test_pyarrow.py adds test_write_file_parquet_round_trip and test_write_file_dispatches_on_write_format_default exercising the full write_file path.

Are there any user-facing changes?

No. Default behavior is unchanged. Setting write.format.default to an unregistered format now raises a ValueError.

[nssalian]

@kevinjqliu @Fokko @geruh PTAL when you can