Model catalog for the OpenRouter provider — a compile-time @models data map, one entry per model, carrying capability and per-million-token pricing metadata (LemonAi.Types.Model / LemonAi.Types.ModelCost). This is data, not logic: the module is long because the catalog is long.

Each entry mirrors a model OpenRouter publishes at https://openrouter.ai/models. The catalog is hand-maintained — there is no live sync task — so it is updated by editing entries here when providers add models or change prices. mix lemon.models lists what is currently defined, and LemonAi.Models merges this map into the unified cross-provider registry.

Originally split out of the monolithic LemonAi.Models in the per-provider decomposition (Debt Phase 5, M2).