Paimon Rest Catalog Server

### Search before asking

- [x] I searched in the [issues](https://github.com/apache/paimon/issues) and found nothing similar.

### Motivation

Hello Teacher Jinsong, we currently have a demand for Paimon Rest Catalog Server. Does the community have any development and open source plans for this area?
If there are ready-made code engineering modules, we would like to participate in testing and development to accelerate the stable development of this logic.
@JingsongLi

### Solution

_No response_

### Anything else?

_No response_

### Are you willing to submit a PR?

- [x] I'm willing to submit a PR!

The issue names no files, tests, or entry points. First clarify the intended Paimon REST Catalog Server scope, existing modules, and expected API behavior with the community. Done should include an agreed implementation plan and a clearly defined server that can be tested for the requested catalog operations.

Written by the indexing model from the issue text.