chore: reorganize playground

source/components/host/stylesheet/details.mjs

source/components/host/stylesheet/host.mjs

source/components/host/stylesheet/overlay.mjs

source/components/host/stylesheet/toggle-button.mjs

source/components/host/stylesheet/viewer.mjs

source/components/layout/split-screen.mjs

source/components/layout/style/width-toggle.pcss

source/components/layout/stylesheet/tabs.mjs

source/components/layout/stylesheet/width-toggle.mjs

source/components/layout/width-toggle.mjs

source/components/stylesheet/property.mjs

theme-generator/package.json

theme-generator/pnpm-lock.yaml

theme-generator/source/index.html

theme-generator/source/main.mjs