[Feature Request]: Raptor summary optimize

[hehemagic]

Is there an existing issue for the same feature request?

• I have checked the existing issues.

Is your feature request related to a problem?

Describe the feature you'd like

Due to the max_length of LLM, raptor may remove some content when summarizing, which may result in some information loss. Can we change it to map-reduce progress, which would be more user-friendly for large documents

Describe implementation you've considered

No response

Documentation, adoption, use case

Additional information

No response