## Summary
- guard Agent pages against malformed model provider/model values before
trimming
- reuse a shared model-ref normalizer across Agent detail, sidebar,
list, and create flows
- add regression coverage for malformed catalog and config entries
## Validation
- `cd site && pnpm exec vitest run
src/pages/AgentsPage/modelOptions.test.ts
src/pages/AgentsPage/AgentDetail.test.ts`
- `cd site && pnpm lint:types`