Add Iceberg Pluggable table format managed directly by Hudi

### Feature Request / Improvement

Feature Request: Support for Pluggable Table Format in Apache Hudi

Apache Hudi is introducing a pluggable table format to enable interoperability with other popular table formats like Iceberg, Delta Lake, and Lance. This allows external engines (e.g., Snowflake) to write to Hudi tables using their native formats while maintaining compatibility. The design focuses on decoupling metadata and storage layers, inspired by Snowflake's metadata architecture. This enhancement supports the modular, composable lakehouse model and promotes broader ecosystem adoption.

I will add the PR to integrate Iceberg plugin for this.

### Are you willing to submit PR?

- [x] Yes I am willing to submit a PR!

### Code of Conduct

- [x] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

Start by reviewing the repository's existing table-format interoperability design and the planned Iceberg plugin described in this issue. Define the integration boundaries for metadata and storage, then confirm that external engines can use the managed Iceberg table format while preserving compatibility with Hudi tables.

Written by the indexing model from the issue text.