Add `uv` package manager for chemX repos

[ozzzzz]

Current "cool" python package manager is https://github.com/astral-sh/uv.

DoD: setup uv for the following packages:

• https://github.com/ai-chem/ChemX
• https://github.com/ai-chem/ChemX-RAG
• https://github.com/ai-chem/ChemX-backend (need @dmitrav ?)
• https://github.com/ai-chem/ChemX-dbt (need @dmitrav ?)

[ozzzzz]

https://github.com/ai-chem/ChemX-RAG/pull/13