[fluss-client] Missing fluss-client JAR in Maven Central

### Search before asking

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

### Fluss version

main (development)

### Please describe the bug 🐞

Hey guys,

I’d like to report that after the migration of the [Maven Central repository for Fluss](https://mvnrepository.com/artifact/org.apache.fluss), the `fluss-client` JAR is missing from the repository.

Could you please check?

Thanks!

### Solution

_No response_

### Are you willing to submit a PR?

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

Start by checking the Fluss Maven Central publication setup for the fluss-client artifact and compare it with the repository’s other published artifacts. Confirm the artifact is present and retrievable from Maven Central after the migration; the issue names no files or tests to use as a more specific entry point.

Written by the indexing model from the issue text.