- Add MiniMax-M3 to the model selection list (set as new default at top)
- Retain MiniMax-M2.7 and MiniMax-M2.7-highspeed
- Remove deprecated MiniMax-M2.5 / M2.5-highspeed
- Update supportsImageInput: M3 supports image input (M2.x stay text-only)
- Update unit tests to reflect new model lineup
- Update example AI_MODEL in CN/EN/JA docs to MiniMax-M3
Co-authored-by: octo-patch <octo-patch@github.com>