[python] Validate write column schema types

[discivigour]

Purpose

Fix schema validation for partial-column writes in paimon-python.

Previously, when with_write_type(...) was used, _validate_pyarrow_schema accepted input as long as the input field names matched write_cols, without checking the corresponding table field types. This could allow an inferred int64 Arrow column to be written into an int32 table column.

Tests

• test_column_subset_write_rejects_int64_for_int32()

[JingsongLi]

+1