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/admin-sidebar.tsx

@@ -2,6 +2,7 @@
 
 import { useState } from 'react'
 import Link from 'next/link'
+import type { Route } from 'next'
 import { usePathname } from 'next/navigation'
 import { signOut } from 'next-auth/react'
 import { cn } from '@/lib/utils'
@@ -29,6 +30,7 @@ import {
   Handshake,
   FileText,
   CircleDot,
+  GraduationCap,
   History,
   User,
 } from 'lucide-react'
@@ -66,6 +68,11 @@ const navigation = [
     href: '/admin/users' as const,
     icon: Users,
   },
+  {
+    name: 'Mentors',
+    href: '/admin/mentors' as const,
+    icon: GraduationCap,
+  },
   {
     name: 'Reports',
     href: '/admin/reports' as const,
@@ -176,7 +183,7 @@ export function AdminSidebar({ user }: AdminSidebarProps) {
               return (
                 <Link
                   key={item.name}
-                  href={item.href}
+                  href={item.href as Route}
                   onClick={() => setIsMobileMenuOpen(false)}
                   className={cn(
                     'group flex items-center gap-3 rounded-lg px-3 py-2.5 text-sm font-medium transition-all duration-150',
@@ -278,7 +285,7 @@ export function AdminSidebar({ user }: AdminSidebarProps) {
 
               <DropdownMenuItem asChild>
                 <Link
-                  href="/admin/settings"
+                  href={"/settings/profile" as Route}
                   className="flex cursor-pointer items-center gap-2.5 rounded-md px-2 py-2"
                 >
                   <User className="h-4 w-4 text-muted-foreground" />