fix(arrow-data): account for struct parent offsets

[jaideeppyne]

Closes #10933.

Struct ArrayData parent offsets compose with child offsets, but a few paths were still treating child data as if parent offset were always zero. This updates:

• struct child validation to require offset + len child elements
• struct equality to compare child values at parent_offset + logical_start
• struct MutableArrayData extension to copy from the parent-offset-adjusted child range

The regression tests cover the concrete cases from #10933: validation, equality, and MutableArrayData::try_extend.

Validation run locally:

cargo test -p arrow-data --lib
cargo fmt --check
cargo clippy -p arrow-data --lib --tests -- -D warnings

[Rich-T-kid]

This PR seems to have introduces a bug in test_struct_array_from_data_with_offset_and_length_error

[jaideeppyne]

Fixed in 79b9203. I updated the struct ArrayData offset/length regression expectation so it now asserts the new validation error instead of expecting the old late panic. Local validation passed (cargo test -p arrow-array test_struct_array_from_data_with_offset_and_length_error --lib, cargo test -p arrow-data --lib, cargo fmt --check), and the GitHub checks are now green.

[Rich-T-kid]

looks good to me.

[jaideeppyne]

Thanks for the review.

[Jefffrey]

thanks @jaideeppyne & @Rich-T-kid