Add initial PCB design#22

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nbelzer wants to merge 23 commits intojhoff:mainfrom

Commits on Apr 30, 2025

Add 3.3v line for PCF8575
nbelzer
committed

Commits on May 15, 2025

Correct AP2112K capacitors
nbelzer
committed

Commits on May 28, 2025

Add pull-ups between PCF8575 and ULN2003
nbelzer
committed

Commits on Jun 3, 2025

Commits on Oct 11, 2025

Commits on Nov 14, 2025

Update pin and header parts
nbelzer
committed

Commits on Nov 16, 2025