docs: fix typo, add gitignore, remove obsolet MANIFEST.in #418

Job	Run time
Tests on OS ubuntu-latest with Python 3.9 and JIT 0	17m 33s
Tests on OS ubuntu-latest with Python 3.9 and JIT 1	10m 49s
Tests on OS ubuntu-latest with Python 3.12 and JIT 0	14m 4s
Tests on OS ubuntu-latest with Python 3.12 and JIT 1	9m 53s
Tests on OS macos-latest with Python 3.9 and JIT 0	10m 12s
Tests on OS macos-latest with Python 3.9 and JIT 1	8m 54s
Tests on OS macos-latest with Python 3.12 and JIT 0	14m 40s
Tests on OS macos-latest with Python 3.12 and JIT 1	12m 10s
Tests on OS windows-latest with Python 3.9 and JIT 0	14m 33s
Tests on OS windows-latest with Python 3.9 and JIT 1	38m 39s
Tests on OS windows-latest with Python 3.12 and JIT 0	15m 31s
Tests on OS windows-latest with Python 3.12 and JIT 1	16m 58s
	3h 3m 56s

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