Inference management UI in the operations dashboard

The operations dashboard now ships an Inference section. It adds Profiles and Providers index pages, profile and token detail pages, usage widgets with period-aware charts, in-dashboard flows to create or delete providers, create tokens, validate model identifiers against the models.dev catalog, and view profile-level client configuration snippets. Local development is also seeded with providers, profiles, tokens, and usage rows so the dashboard has realistic data to explore.