feat: shop 4-section category banners + brand-feedback pass

Shop page rebuilt into four brand colour-coded use-group sections (Küche/lime,
Reinigung/grapefruit, Wäsche/plum, Pflege/care/orange): colour banners with diagonal
dividers, per-section grid titles, crimson 'add to cart' + white-outline 'learn more'
CTAs, plain-name eyebrows, first-fold halved + thin white band. Split old Haushalt
group into clean+wash.

Also in this checkpoint (brand-owner feedback items):
- L11: Kaiser-Natron® on every visible mention, hyphenated (de+en, products, logo, nav)
- L4: product-hero headline reworded to the brand versatility voice
- L5/L6: faint 'AI Edited' badge on AI bundle images (data-driven aiEdited flag)
- L10: Revitalization animation row + early-access CTA removed
- U2: membership 'become a member' button removed
- New category tokens (cat-kitchen/clean/wash/care) + Hero/WaveDivider tones
- New /kueche category page (route + copy) — not yet linked (see STYLE-CHANGES caveat)
- Homepage reverted to original ProductTeaser (banners belong on /shop)

dist/ rebuilt and included for the Portainer/gitea deploy. Open decisions tracked
in STYLE-CHANGES.md §20 and memory.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/pages/CategoryPage.vue

@@ -23,13 +23,13 @@ const props = defineProps({
   slug: {
     type: String,
     required: true,
-    validator: (v) => ['pflege', 'haushalt'].includes(v),
+    validator: (v) => ['pflege', 'haushalt', 'kueche'].includes(v),
   },
-  /** Maps to the existing use-case grouping (clean / care). */
+  /** Maps to the existing use-case grouping (cook / clean / care). */
   useCase: {
     type: String,
     required: true,
-    validator: (v) => ['clean', 'care'].includes(v),
+    validator: (v) => ['cook', 'clean', 'care'].includes(v),
   },
 })