[Subtask] Add event listener support for Semantic Model operations

### Describe the subtask

Add listener events and audit integration for first-class Semantic Model operations.

This includes:

- Add pre, success, and failure events for listing, loading, creating, altering, and dropping Semantic Models.
- Add an immutable `SemanticModelInfo` for listener event payloads.
- Add `SemanticModelEventDispatcher` and wire the dispatcher chain as `SemanticModelEventDispatcher -> SemanticModelNormalizeDispatcher -> SemanticModelOperationDispatcher`.
- Add operation types and audit mappings for Semantic Model events.
- Add focused tests for success and failure events, list result counts, immutable payloads, and audit mappings.

`semanticModelExists` does not need a dedicated event, consistent with the existing View and Function behavior.

Semantic Model ownership and privilege hooks are out of scope and tracked in #12594.

### Parent issue

#12209