Expose Lance tables in DataFusion via namespace

[majin1102]

Integrate datafusion with lance namespace to support multi-table query

How Iceberg integrate datafusion through CatalogProvider:
https://github.com/apache/iceberg-rust/tree/main/crates/integrations/datafusion
How delta integrate datafusion through TableProvider:
https://github.com/delta-io/delta-rs/blob/main/crates/core/src/delta_datafusion/table_provider.rs