fix(datafusion): add error logging to catalog methods that silently swallow errors

[shyjsarah]

…wallow errors

The CatalogProvider/SchemaProvider trait methods schema_names(), schema(), table_names(), and table_exist() have no Result return type, so errors from remote catalog operations were silently discarded. Add log::error! to surface these failures for debugging.

Purpose

Linked issue: N/A (no existing issue — upstream trait limitation)

Add log::error! to 4 CatalogProvider/SchemaProvider trait methods that silently discard errors from remote catalog operations, making failures visible for debugging.

Brief change log

• schema_names(): replace unwrap_or_default() with match + log::error! on Err
• schema(): replace Err(_) => None with log::error! before returning None
• table_names(): replace unwrap_or_default() with match + log::error! on Err
• table_exist(): replace Err(_) => false with log::error! before returning false
• Add log = "0.4" dependency to paimon-datafusion

These 4 methods have no Result return type in the upstream DataFusion trait, so logging is the best we can do. A proper fix requires changing the upstream trait signatures (to
be proposed separately as a breaking API change on apache/datafusion).

Tests

• Existing tests pass (cargo test -p paimon-datafusion)
• Manual: set RUST_LOG=error and trigger a catalog error to verify log output

API and Format

No API or format changes.

Documentation

No documentation changes needed.

[JingsongLi]

+1