Models settings section plugin: registers the `models` nav entry into `settings.section` with an intentionally empty content column — model management lands in a later phase.
## Model Experience
None, as the section renders an empty browser UI column; nothing here reaches a model request.
#### KV Cache effect
None; this package neither assembles nor sends a provider request.
## Known Limitations and Deferred Work
- **Content column is empty by design** — provider list, editing form, and activation flow are deferred until the model-management service exists.
