Reject providers with no models into bad_providers and warn with reasons on chat/providers. When /provider changes and the current model is not listed, prompt for a new model (keep it when still supported).
When preset deepseek omits models, seed deepseek-v4-flash and deepseek-v4-pro as text-capable entries for selection and docs.
Parse and expose [database] with defaults; keep providers API unchanged.
NCBM