[Subtask] Add Semantic Model list, alter, and drop REST APIs in Gravitino

### Describe the subtask

Add REST APIs for listing, altering, and dropping Semantic Models, including atomic alter request DTOs, conversion to Semantic Model changes, server routing, and focused tests.

The alter API supports rename, comment update, property changes, and definition replacement. Create, load, OpenAPI, and clients are out of scope.

### Parent issue

#12209

Start by tracing the existing server REST routing and analogous resource APIs. Cover listing, altering, and dropping Semantic Models, including atomic alter request DTOs and conversion to Semantic Model changes; add focused tests for these paths. Keep create, load, OpenAPI, and client work out of scope.

Written by the indexing model from the issue text.