feat: move to mystmd #2256

Job	Run time
change-detection / Identify source changes	9s
rr-tests / Run pylint	14s
rr-tests / Run cog on README	9s
cookie / Format	8m 16s
rr-tests / Action	17s
cookie / Check Python 3.14 on macos-15-intel	6m 57s
cookie / Check Python 3.14 on macos-latest	2m 3s
rr-tests / Check Python 3.14 on macos-15-intel	1m 28s
cookie / Distribution build	10m 29s
cookie / Check Python 3.10 on macos-latest	1m 43s
rr-tests / Check Python 3.10 on macos-latest	56s
cookie / Check Python 3.10 on ubuntu-latest	3m 49s
rr-tests / Check Python 3.12 on ubuntu-latest	33s
rr-tests / Check Python 3.10 on windows-latest	55s
rr-tests / Check Python 3.12 on macos-latest	29s
cookie / Check Python 3.14 on ubuntu-latest	4m 17s
rr-tests / Check Python 3.14 on ubuntu-latest	38s
cookie / Check Python 3.10 on windows-latest	5m 49s
rr-tests / Check Python 3.12 on macos-15-intel	1m 7s
cookie / Check Python 3.14 on windows-latest	5m 36s
cookie / Check included Noxfile	37s
rr-tests / Check Python 3.10 on ubuntu-latest	35s
cookie / Check Python 3.10 on macos-15-intel	3m 29s
rr-tests / Check Python 3.14 on windows-latest	50s
rr-tests / Check Python 3.10 on macos-15-intel	1m 13s
rr-tests / Check Python 3.14 on macos-latest	35s
cookie / Check Python pypy-3.11 on ubuntu-latest	2m 27s
rr-tests / Check Python 3.12 on windows-latest	1m 2s
cookie / pass	4s
pass	5s
	1h 6m 51s

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