- Add changePreferredProviderType contract in model-providers.ts
- Register in consoleRouterContract
- Replace raw async changeModelProviderPriority with useMutation
- Use Toast.notify (static API) instead of useToastContext hook
- Pass isPending as isChangingPriority to disable buttons during switch
- Add disabled prop to UsagePrioritySection
- Fix pre-existing test assertions for api-unavailable variant
- Update all specs with isChangingPriority prop and oRPC mock pattern