Update ai-experience plugin to query AiModelServerAPI entities

Summary

After PR #4211 (issue #4209), the model catalog entity provider emits AiModelServerAPI entities with spec.type: 'ai-model-server' instead of the previous Resource entities with spec.type: 'ai-model' (plus Component and API entities). The ai-experience plugin still queries for the old entity shapes and needs to be updated.

Affected code

1. plugins/ai-experience-backend/src/services/ModelService/ModelService.ts:73-74 — queries { kind: 'Resource', 'spec.type': 'ai-model' }, which will return zero results after the entity provider change.

2. plugins/ai-experience/src/components/ModelSection/ModelSection.tsx:54-55 — builds a catalog link with filters[kind]=resource&filters[type]=ai-model, which will show no results in the UI.

What to change

Update both locations to query for { kind: 'AiModelServerAPI', 'spec.type': 'ai-model-server' } and adjust any response handling for the new entity shape (models are now in spec.models.available instead of being separate Resource entities).

Context

• PR #4211 / issue #4209 introduced the AiModelServerAPI kind
• The ai-experience plugin is expected to be replaced, but should be updated in the interim to avoid a broken model section

Start with plugins/ai-experience-backend/src/services/ModelService/ModelService.ts:73-74 and plugins/ai-experience/src/components/ModelSection/ModelSection.tsx:54-55, then review PR #4211 or issue #4209 for the AiModelServerAPI entity shape. Update both queries and response handling for spec.models.available, and verify that the model section displays the available models and its catalog link returns results.