Unxt

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
* feat: generalize select_n dispatch by nstarman in https://github.com/GalacticDynamics/unxt/pull/275
* fix: extend unitsystems with one unit string by nstarman in https://github.com/GalacticDynamics/unxt/pull/276
* ci: format docstring code by nstarman in https://github.com/GalacticDynamics/unxt/pull/277
* refactor: simplify code and docs by nstarman in https://github.com/GalacticDynamics/unxt/pull/278
* Docs add comments by nstarman in https://github.com/GalacticDynamics/unxt/pull/279
* ci: install docs group separately by nstarman in https://github.com/GalacticDynamics/unxt/pull/280


**Full Changelog**: https://github.com/GalacticDynamics/unxt/compare/v0.20.5...v0.20.6

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
* feat: scan_p by nstarman in https://github.com/GalacticDynamics/unxt/pull/273


**Full Changelog**: https://github.com/GalacticDynamics/unxt/compare/v0.20.4...v0.20.5

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
* fix: comparison ops by nstarman in https://github.com/GalacticDynamics/unxt/pull/245
* ci: enable offline docs builds by nstarman in https://github.com/GalacticDynamics/unxt/pull/266
* fix: add cgs to unit system instances by nstarman in https://github.com/GalacticDynamics/unxt/pull/267
* feat: improve builtin usys by nstarman in https://github.com/GalacticDynamics/unxt/pull/268
* feat: improve SingletonMixin by nstarman in https://github.com/GalacticDynamics/unxt/pull/269
* feat: make SI, CGS singletons by nstarman in https://github.com/GalacticDynamics/unxt/pull/270
* feat: dynamic_slice_p by nstarman in https://github.com/GalacticDynamics/unxt/pull/272


**Full Changelog**: https://github.com/GalacticDynamics/unxt/compare/v0.20.3...v0.20.4

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
* feat: add ravel by nstarman in https://github.com/GalacticDynamics/unxt/pull/256
* fix: cleanup by nstarman in https://github.com/GalacticDynamics/unxt/pull/257
* feat: dimensions_of None by nstarman in https://github.com/GalacticDynamics/unxt/pull/258
* docs: add to dims by nstarman in https://github.com/GalacticDynamics/unxt/pull/259
* feat: units_of things without units returns None by nstarman in https://github.com/GalacticDynamics/unxt/pull/260
* ci: stop skipping windows by nstarman in https://github.com/GalacticDynamics/unxt/pull/261
* build: swith to pep 735 by nstarman in https://github.com/GalacticDynamics/unxt/pull/262
* ci: test oldest dependencies by nstarman in https://github.com/GalacticDynamics/unxt/pull/263
* ci: include pypy by nstarman in https://github.com/GalacticDynamics/unxt/pull/264
* ci: add benchmark tests by nstarman in https://github.com/GalacticDynamics/unxt/pull/265

**Full Changelog**: https://github.com/GalacticDynamics/unxt/compare/v0.20.2...v0.20.3

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
* docs: update docstrings by nstarman in https://github.com/GalacticDynamics/unxt/pull/250
* refactor: use abstracts for dimensions by nstarman in https://github.com/GalacticDynamics/unxt/pull/251
* test: add nox config by nstarman in https://github.com/GalacticDynamics/unxt/pull/252
* docs: rm returns by nstarman in https://github.com/GalacticDynamics/unxt/pull/253
* feat: add dims sub-package by nstarman in https://github.com/GalacticDynamics/unxt/pull/254
* Fix: linespace and experimental by nstarman in https://github.com/GalacticDynamics/unxt/pull/255


**Full Changelog**: https://github.com/GalacticDynamics/unxt/compare/v0.20.1...v0.20.2

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
* build: bump deps by nstarman in https://github.com/GalacticDynamics/unxt/pull/247
* feat: IPython repr by nstarman in https://github.com/GalacticDynamics/unxt/pull/248
* test: simplify test_quantity by nstarman in https://github.com/GalacticDynamics/unxt/pull/249


**Full Changelog**: https://github.com/GalacticDynamics/unxt/compare/v0.20.0...v0.20.1