🧹 cleanup

[chase-moskal]

• [x] stop unnecessarily rebuilding the bundle in the dev watch routine (since we are using es-module-shims)
• [x] let's do some renaming
  • maybe rename main.ts to humanoid.ts
  • extract website homepage script to website.ts
• [x] rethink s/demo
• [x] reorganize s/thumbtastic/ (into a toolbox?) and upgrade xiome and fix thumbtastic.ts <any>
• [x] add .github/CODEOWNERS to require me to approve any changes to deployments