[Subtask] Add built-in IdP user meta storage model

### Describe the subtask

Add the built-in IdP user metadata relational storage model under `plugins:idp-basic`, including the user persistent object, MyBatis mapper, SQL provider factory, backend-specific SQL providers, mapper registration, and corresponding tests.

Related PR: https://github.com/apache/gravitino/pull/11066

### Parent issue

https://github.com/apache/gravitino/issues/10959
