Enhance email templates with clickable links, branding, and improved styling

- Add clickable gallery links in all email templates
- Include application logo in email header and footer (custom or PicPeak default)
- Redesign emails with professional styling matching gallery login page
  - Gray background with white content box
  - PicPeak green header with centered logo
  - Clean typography and proper spacing
  - Responsive design for mobile devices
  - Styled call-to-action buttons
  - Footer with branding and copyright
- Update email processor to fetch branding settings dynamically
- Use proper API URLs for logo images in emails

🤖 Generated with [Claude Code](https://claude.ai/code)

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

frontend/src/types/index.ts

@@ -5,6 +5,7 @@ export interface Event {
   event_type: string;
   event_name: string;
   event_date: string;
+  host_name?: string;
   host_email: string;
   admin_email: string;
   welcome_message?: string;
@@ -26,6 +27,10 @@ export interface Event {
   }>;
   allow_user_uploads?: boolean;
   upload_category_id?: number | null;
+  hero_photo_id?: number | null;
+  total_views?: number;
+  total_downloads?: number;
+  unique_visitors?: number;
 }
 
 export interface GalleryInfo {
@@ -36,6 +41,7 @@ export interface GalleryInfo {
   is_active: boolean;
   is_expired: boolean;
   requires_password?: boolean;
+  color_theme?: string;
 }
 
 export interface Photo {
@@ -69,6 +75,7 @@ export interface GalleryData {
     expires_at: string;
     allow_user_uploads?: boolean;
     upload_category_id?: number | null;
+    hero_photo_id?: number | null;
   };
   categories?: PhotoCategory[];
   photos: Photo[];