feat: implement Marco's customer changes

- Remove 'Flotte ansehen' button from hero section
- Remove '24/7 Support' stat from hero section
- Remove 'Unsere Flotte' eyebrow from fleet section
- Remove ALL 'Warum wir' / 'Why us' references from nav links, i18n keys, and legal pages
- Update reviews: Ferrari references only (removed GT3 mentions)
- Update Impressum with correct company data (MC Cars GmbH)
- Add multi-photo gallery: DB migration (17-vehicle-photos.sql), admin UI for photo management, frontend carousel on cards and dialog
- Update SEO: Ferrari-focused meta tags, title, keywords, JSON-LD
- Clean up dead i18n keys (viewFleet, statSupport, fleetEyebrow, navWhy, why* keys)
- Fix legal page issues: add config.js script, fix logo references to SVG
- Add Playwright E2E tests (26/26 passing)
- Update footer tagline across all pages

frontend/admin.html

@@ -172,11 +172,19 @@
 
                         <div class="admin-photo-preview" id="photoPreview"></div>
                         <label>
-                            <span data-i18n="adminPhotoUpload">Foto hochladen (JPG/PNG/WebP, max 50 MB)</span>
+                            <span data-i18n="adminPhotoUpload">Hauptfoto hochladen (JPG/PNG/WebP, max 50 MB)</span>
                             <input type="file" id="photoInput" accept="image/*" />
                         </label>
                         <input type="hidden" name="photo_url" />
 
+                        <div style="margin-top:1.2rem;">
+                            <label>
+                                <span>Weitere Fotos hinzufügen</span>
+                                <input type="file" id="extraPhotoInput" accept="image/*" multiple />
+                            </label>
+                            <div id="extraPhotoGallery" style="display:grid;grid-template-columns:repeat(auto-fill,minmax(100px,1fr));gap:0.5rem;margin-top:0.5rem;"></div>
+                        </div>
+
                         <div class="row2">
                             <label><span data-i18n="adminBrand">Marke</span><input name="brand" required /></label>
                             <label><span data-i18n="adminModel">Modell</span><input name="model" required /></label>