plan: remove support for older platforms

[henryiii]

After the recent release, I'd like to increase the minimum requirements:

• Require Python 3.7+ for the Python bindings
• Require CMake 3.18+ (or newer, based on what is easy to support - installing a new CMake up to 3.22 is trivial)
• Require a recent version of CUDA (probably 11.3+)
• Update Thrust (seems to work on recent CUDA?)
• Require a version of ROOT from the last couple of years
• Default (probably not require quite yet?) to at least C++14
• Probably require a newer GCC than we do now

We are currently paying a huge technical debt for old platform support that is keeping us from supporting the newer platforms properly (like CUDA 10.2+).

Plan:

• Restore pre-commit chore: update pre-commit hooks #344
• Drop Python < 3.6 feat: drop old Python up to Python 3.6 #343
• Update CLI11 2.3 chore: update to CLI11 2.3.2 #342
• Move to Ruff chore: move to using Ruff #354
• Update ROOT C++17 chore: bump ROOT, C++17 #324
• Drop the rest chore: drop old platform support #321
• Merge hackathon changes