[tlambert03]

this modernizes the repo tooling a bit, mostly so you can clone and just uv sync (pixi still works too)
closes #79

• switch build backend to hatchling + hatch-vcs. NOTE: there are no tags in the repo yet, so version will be 0.1.devN until we tag something
• move dev/docs extras to dependency groups, and add lower bounds to all deps (to facilitate testing --resolution lowest-direct in ci)
• drop scikit-image, scikit-learn, and pandas (they were declared dependencies but weren't imported anywhere). added matplotlib and tqdm, which were being imported but not declared
• move funlib.learn.torch to the test group... it's only used in tests, and having a git dependency in runtime deps means we can't publish to PyPI
• add a cpu dependency group (uv sync --group cpu) that pulls torch from the pytorch CPU index. default uv sync still gets torch from PyPI (which is CUDA on linux)
• pre-commit changed to prek, with the usual ruff settings. mypy and typos config moved into pyproject. removed .cruft.json, mypy.ini, _typos.toml
• new ci.yml using setup-uv: tests py3.10-3.14 on both highest and lowest-direct resolution, and runs prek run -a in one of the jobs. the lowest-direct jobs use uv pip compile --no-build, so we don't need per-python lower bounds in pyproject
• docs deploy now uses uv instead of conda
• lint fixes across the codebase (one commit of ruff autofixes, one of manual fixes, split up to make review easier)
• use imageio.v2 to silence the deprecation warning
• README/install docs updated to drop the .[dev] stuff