style(ui): full UX/UI + motion pass across storefront, admin, editor

- fix save-bar buttons to use shared app-button primitive (were unstyled)
- fix platform-nav-group border/radius via structural selectors, drop dead
  -middle/-right classes
- storefront widgets (hero/categories/product-carousel/footer-nav): design
  tokens, hover/focus states, 44px touch targets, entrance motion, reduced-
  motion guards
- admin dashboard cards + quick-actions: hover lift, entrance animation
- admin product-form gallery remove badge: hover/focus + expanded hit area
- project-editor section.shared button styles: hover/active/focus/disabled
  states + reduced-motion; section-switch fade-in motion

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/components/header/header.component.html

@@ -11,17 +11,17 @@
       <!-- Navigation Buttons (desktop) -->
       <nav class="platform-nav">
         <div class="platform-nav-group">
-          <a [routerLink]="'/' | langRoute" routerLinkActive="platform-active" [routerLinkActiveOptions]="{exact: true}" 
-             (click)="closeMenu()" class="platform-nav-btn platform-nav-btn-left">
+          <a [routerLink]="'/' | langRoute" routerLinkActive="platform-active" [routerLinkActiveOptions]="{exact: true}"
+             (click)="closeMenu()" class="platform-nav-btn">
             {{ 'header.home' | translate }}
           </a>
           @if (headerConfig().showCategories) {
-            <button type="button" (click)="navigateToCatalog()" class="platform-nav-btn platform-nav-btn-left">
+            <button type="button" (click)="navigateToCatalog()" class="platform-nav-btn">
               {{ 'header.catalog' | translate }}
             </button>
           }
           @for (page of headerPages(); track page.id) {
-            <button type="button" (click)="navigateToStatic(page.route)" class="platform-nav-btn platform-nav-btn-left">
+            <button type="button" (click)="navigateToStatic(page.route)" class="platform-nav-btn">
               {{ page.title }}
             </button>
           }