[Feature] Support Lance file format

[wangyong9999]

Search before asking

• I searched in the issues and found nothing similar.

Motivation

Apache Paimon Java supports Lance as a data file format through the paimon-lance module. Paimon C++ currently cannot read or write tables configured with file.format=lance, which prevents Java and C++ engines from interoperating on those tables.

Solution

Add optional Lance file format support to Paimon C++, aligned with the Java implementation and Lance 0.39.0:

• register a Lance file format factory behind a disabled-by-default CMake option;
• support reading and writing Lance files through the existing file format interfaces;
• support column projection, precise row selection, row counts, and file row-id reporting;
• validate the same supported and unsupported logical types as Java;
• add C++ round-trip tests and Java/C++ compatibility fixtures in both directions.

The implementation should follow the existing Mosaic Rust FFI integration and lifecycle patterns.

Anything else?

Java reference module: https://github.com/apache/paimon/tree/master/paimon-lance

Are you willing to submit a PR?

• I am willing to submit a PR!