Add profile settings page, mentor management, and S3 email logos

- Add universal /settings/profile page accessible to all roles with
  avatar upload, bio, phone, password change, and account deletion
- Expand updateProfile endpoint to accept bio (metadataJson), phone,
  and notification preference
- Add deleteAccount endpoint with password confirmation
- Add Profile Settings link to all nav components (admin, jury, mentor,
  observer)
- Add /admin/mentors list page and /admin/mentors/[id] detail page for
  mentor management
- Add Mentors nav item to admin sidebar
- Update email logo URLs to S3 (s3.monaco-opc.com/public/)
- Add ocean.png background image to email wrapper

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/layouts/observer-nav.tsx

@@ -14,7 +14,8 @@ import {
   DropdownMenuSeparator,
   DropdownMenuTrigger,
 } from '@/components/ui/dropdown-menu'
-import { Home, BarChart3, Menu, X, LogOut, Eye } from 'lucide-react'
+import type { Route } from 'next'
+import { Home, BarChart3, Menu, X, LogOut, Eye, Settings } from 'lucide-react'
 import { getInitials } from '@/lib/utils'
 import { Logo } from '@/components/shared/logo'
 
@@ -92,6 +93,13 @@ export function ObserverNav({ user }: ObserverNavProps) {
                 {user.email}
               </DropdownMenuItem>
               <DropdownMenuSeparator />
+              <DropdownMenuItem asChild>
+                <Link href={"/settings/profile" as Route} className="flex cursor-pointer items-center">
+                  <Settings className="mr-2 h-4 w-4" />
+                  Profile Settings
+                </Link>
+              </DropdownMenuItem>
+              <DropdownMenuSeparator />
               <DropdownMenuItem
                 onClick={() => signOut({ callbackUrl: '/login' })}
                 className="text-destructive focus:text-destructive"