* new: drop python 3.8 support, update type hints
* fix: remove 3.8 from ci
* fix: update type hints
* fix: make netlify use python3.10
* fix: try python3.9 for sphinx
* debug: try updating sphinx
* new: bump ffastembed to 0.4.2
* fix: install numpy<2 for mypy
* fix: install numpy via poetry
* tests: add some values count congruence tests
* fix: fix incorrect behaviour of value_counts, isempty, isnull in local mode
* fix: update isempty behaviour
* tests: add test cases for isnull and isempty