refactor: replace `AnyFunction` by proper types #231

Job	Run time
checks / pre-commit	31s
checks / readme-snippets	12s
checks / test (3.11, lowest-direct, windows-latest)	2m 30s
checks / test (3.10, locked, ubuntu-latest)	46s
checks / test (3.10, lowest-direct, windows-latest)	2m 26s
checks / test (3.11, locked, windows-latest)	2m 31s
checks / test (3.12, locked, ubuntu-latest)	56s
checks / test (3.13, locked, windows-latest)	2m 27s
checks / test (3.12, lowest-direct, ubuntu-latest)	51s
checks / test (3.12, locked, windows-latest)	3m 56s
checks / test (3.11, lowest-direct, ubuntu-latest)	46s
checks / test (3.14, locked, ubuntu-latest)	2m 24s
checks / test (3.14, lowest-direct, ubuntu-latest)	1m 14s
checks / test (3.10, lowest-direct, ubuntu-latest)	49s
checks / test (3.13, lowest-direct, windows-latest)	2m 25s
checks / test (3.12, lowest-direct, windows-latest)	3m 24s
checks / test (3.13, lowest-direct, ubuntu-latest)	45s
checks / test (3.14, locked, windows-latest)	3m 34s
checks / test (3.13, locked, ubuntu-latest)	46s
checks / test (3.10, locked, windows-latest)	2m 25s
checks / test (3.14, lowest-direct, windows-latest)	2m 44s
checks / test (3.11, locked, ubuntu-latest)	43s
all-green	4s
	39m 9s

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