Product surface

Piece	Role
/config/design-system	Only workspace (Appearance + Live Preview)
design-system/+page.svelte	Tabs: overrides, preview, themes, presets, layout, style, …
design-system-preview.svelte	Live Preview component catalog
appearance-api.ts	Theme CRUD + prefs via fetchApi (CSRF)
/user Settings	Quick density/variant strip + link to ?tab=overrides

Control → test matrix

Control	Unit	E2E
User prefs save/clear/reload	appearance-api	✅ appearance.spec
Themes tab shell	—	✅ appearance-golden
Golden create→list→delete	appearance-api	✅ appearance-golden
Live Preview tab	—	✅ design-system.spec
Surface → --admin-bg-card	theme-preset-mapper	unit

Run

bun run test:unit -- tests/unit/config/appearance-api.test.ts tests/unit/theme-preset-mapper.test.ts
bun x playwright test tests/e2e/routes/config/design-system.spec.ts tests/e2e/routes/config/appearance.spec.ts tests/e2e/routes/config/appearance-golden.spec.ts