feat: draft mode, admin branding, and workflow improvements

Draft Mode:
- Events are created as drafts by default — no email sent until published
- Add "Publish & Notify Client" button with confirmation dialog
- Draft banner with yellow styling on event details page
- Draft filter tab in events list
- Gallery middleware blocks public access to draft events
- Migration 076 adds is_draft column to events table

Admin Draft Preview:
- Admins can preview draft galleries via JWT preview token (?preview=)
- "View Gallery" link on drafts auto-appends preview token

Admin & Login Page Branding:
- Admin header uses configured company logo/name from branding settings
- Login page shows configured logo instead of hardcoded PicPeak
- Respects logo_display_mode (logo_only, text_only, logo_and_text)

OG Tag Branding:
- DynamicFavicon component updates OG meta tags and page title from
  branding settings

Editable Client Email:
- Customer email is now editable after event creation in edit mode

Branding Inheritance:
- New events inherit hero logo settings (visibility, size, position)
  from global branding configuration

Share Link Full Domain URL:
- New getFrontendBaseUrl() utility with DB fallback to general_site_url
- Used in email processor and share link service

frontend/src/services/events.service.ts

@@ -74,7 +74,7 @@ export const eventsService = {
   async getEvents(
     page: number = 1,
     limit: number = 20,
-    status?: 'active' | 'inactive' | 'archived'
+    status?: 'active' | 'inactive' | 'archived' | 'draft'
   ): Promise<EventsListResponse> {
     const params = new URLSearchParams({
       page: page.toString(),
@@ -173,6 +173,18 @@ export const eventsService = {
     return response.data;
   },
 
+  // Publish a draft event
+  async publishEvent(eventId: number): Promise<{ message: string; is_draft: boolean }> {
+    const response = await api.post(`/admin/events/${eventId}/publish`);
+    return response.data;
+  },
+
+  // Get admin preview token (uses existing admin session token)
+  getPreviewToken(): string | null {
+    const token = sessionStorage.getItem('admin_token') || localStorage.getItem('admin_token');
+    return token;
+  },
+
   // Rename event
   async renameEvent(eventId: number, newEventName: string, resendEmail: boolean = false): Promise<{
     success: boolean;