[Feature] [schema] Add database path for database in paimon

### Search before asking

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

### Motivation

Currently paimon use catalog to manage the top path in file system with option `warehouse`. In our production environment, we always use one catalog named `paimon` to manage all databases and tables in it, and we need to configure independent file system path for each database.

### Solution

_No response_

### Anything else?

_No response_

### Are you willing to submit a PR?

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

Start by tracing how the catalog uses the warehouse option to determine paths for databases and tables. Define how an independent filesystem path would be configured and propagated for each database, then verify that existing catalog and table path behavior remains intact.

Written by the indexing model from the issue text.