Lightweight base `nnsight` installation

[AdamBelfki3]

Possible fixes:

• Leverage setup.py to only install required dependencies dynamically.
• Create optional dependencies stages, e.g. nnsight[vllm], nnsight[remote], nnsight[dev]...etc

[MichaelRipa]

Were you thinking of having pip install nnsight still install all dependencies by default and just provide some alternative light installations? (nnsight[base], nnsight[lm], ...) Or just having pip install nnsight install the bare minimum for the base NNsight class and then provide ways of installing dependencies for different classes (LanguageModel, VLLM etc)