Reduce mandatory dependencies for easier maintainability

[ATheorell]

These are the current (first order) dependencies:

python = ">=3.8.1,<3.12" # updated for llama-index dependency
openai = "0.28"
termcolor = "2.3.0"
typer = ">=0.3.2"
rudder-sdk-python = ">=2.0.2"
dataclasses-json = "0.5.7"
tiktoken = ">=0.0.4"
tabulate = "0.9.0"
python-dotenv = ">=0.21.0"
langchain = ">=0.0.335"

It would be nice to reduce the number of dependencies if possible.

Hypotheses:

• click can replace typer, termcolor and tabulate
  or
• rich can replace termcolor and tabulate
  or
• just remove tabulate

Different note:

• pydantic (already a secondary dependency under langchain) can replace dataclasses-json

Does this make sense? More ideas? This discussion should result in a feature request.