Updated documentation to highlight existence of RAG_USE_FULL_CONTEXT variable

[timmanik]

Currently, there isn't documentation that highlights the ability to use full context of the documents uploaded for RAG. This causes new users like myself to run into subpar RAG results in certain scenarios. Adding documentation for the RAG_USE_FULL_CONTEXT parameter/variable to raise awareness of this feature.

Related discussion: danny-avila/LibreChat#4066

[FinnConnor]

The env variable RAG_USE_FULL_CONTEXT is not apart of of RAG_API. Setting it true or false (within RAG_API) will have no effect. I double checked this by setting RAG_USE_FULL_CONTEXT=false and was able to retrieve 20+ documents (full context) on the GET /documents/{id}/context endpoint. The RAG_API will always return full context. RAG_USE_FULL_CONTEXT is a configuration of LibreChat.

Therefore, changing the documentation of LibreChat not RAG_API is needed. Thanks for bringing this up @timmanik