test: verify nested Iceberg field IDs through Parquet scans

[osipovartem]

Summary

• Write LIST and MAP<STRING, STRUCT> values to an Iceberg Parquet data file.
• Evolve the schema by renaming and reordering nested fields and adding nullable children.
• Read the unchanged file using the current schema and assert values, nulls, container offsets, and map keys.

Verification

• cargo +1.99.0 test -p datafusion_iceberg --test nested_schema_evolution
• cargo +1.99.0 clippy -p datafusion_iceberg --test nested_schema_evolution (with existing Rust 1.99 lint exceptions)
• cargo +1.99.0 fmt --all --check
• Independent read-only review: approved, no blocking findings.

Test-only change; live Horizon/SPCS validation remains separate.