fix(project-editor): validate footer payment/social links, add footer logo picker

- header-section: raw checkboxes -> app-toggle, wrap in SectionCard
- footer-section: replace unvalidated pipe-delimited textareas for payment
  icons/social links with KeyValueEditor + MediaPickerComponent, add missing
  footer logo picker, validate social link URLs (http/https), wrap in SectionCard
- i18n: add footer logo / key-value-editor labels and URL validation message

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/features/project-editor/sections/header-section.component.ts

@@ -3,11 +3,13 @@ import { FormsModule } from '@angular/forms';
 import { ProjectEditorFacade } from '../facade/project-editor.facade';
 import { TranslatePipe } from '../../../i18n/translate.pipe';
 import { HeaderConfig } from '../../../shared/models/config';
+import { SectionCardComponent } from '../../../shared/ui/section-card/section-card.component';
+import { ToggleComponent } from '../../../shared/ui/toggle/toggle.component';
 
 @Component({
   selector: 'app-project-editor-header-section',
   standalone: true,
-  imports: [FormsModule, TranslatePipe],
+  imports: [FormsModule, TranslatePipe, SectionCardComponent, ToggleComponent],
   templateUrl: './header-section.component.html',
   styleUrls: ['./section.shared.scss'],
   changeDetection: ChangeDetectionStrategy.OnPush