Verify display pricing against the official pricing page and the live
provider model list:
- add claude-fable-5-1 and deepseek/deepseek-v4-flash-fast
- remove minimax/minimax-m3-free and minimax/minimax-m2.7-free, which the
provider no longer lists
- end the claude-sonnet-5 introductory window; the listed rate is unchanged
- google/gemini-3.7-flash returns to list price after the promotion ended