Fix conda env create failures on modern conda/pip

[KaningNoppasin]

Summary

This PR fixes environment creation issues reported when running:

conda env create -f environment.yml

Changes

• Pin pip to 23.3 in environment.yml
• Pin wheel to 0.37 in environment.yml
• Add troubleshooting note in INSTALL.md for conda CUDA/cache permission issues using:
  • XDG_CACHE_HOME=$PWD/.cache CONDA_OVERRIDE_CUDA=''

Root cause

• gym==0.21.0 (installed via pip extras) fails to build with newer wheel versions because of legacy requirement metadata parsing.
• Some conda setups also crash during CUDA virtual package detection/cache access.

Validation

• Recreated tf2 environment successfully end-to-end with updated files.