Restructure to Karpathy 3-layer format

c4d80c7215be tmad4000 2026-04-12

Update schema.md

c9ea7da66c07 jeremynixon 2026-04-11

Update schema.md

68ee2ceb1f44 jeremynixon 2026-04-11

Initial wiki scaffold

f87101aa79b4 wikihub 2026-04-10