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/app/(settings)/layout.tsx

@@ -0,0 +1,55 @@
+import { redirect } from 'next/navigation'
+import { auth } from '@/lib/auth'
+
+const ROLE_DASHBOARDS: Record<string, string> = {
+  SUPER_ADMIN: '/admin',
+  PROGRAM_ADMIN: '/admin',
+  JURY_MEMBER: '/jury',
+  MENTOR: '/mentor',
+  OBSERVER: '/observer',
+}
+
+export default async function SettingsLayout({
+  children,
+}: {
+  children: React.ReactNode
+}) {
+  const session = await auth()
+
+  if (!session?.user) {
+    redirect('/login')
+  }
+
+  const dashboardUrl = ROLE_DASHBOARDS[session.user.role] || '/login'
+
+  return (
+    <div className="min-h-screen bg-background">
+      <header className="sticky top-0 z-40 border-b bg-card">
+        <div className="container mx-auto flex h-16 max-w-3xl items-center px-4">
+          <a
+            href={dashboardUrl}
+            className="flex items-center gap-2 text-sm font-medium text-muted-foreground transition-colors hover:text-foreground"
+          >
+            <svg
+              xmlns="http://www.w3.org/2000/svg"
+              width="16"
+              height="16"
+              viewBox="0 0 24 24"
+              fill="none"
+              stroke="currentColor"
+              strokeWidth="2"
+              strokeLinecap="round"
+              strokeLinejoin="round"
+            >
+              <path d="m15 18-6-6 6-6" />
+            </svg>
+            Back to Dashboard
+          </a>
+        </div>
+      </header>
+      <main className="container mx-auto max-w-3xl px-4 py-6 lg:py-8">
+        {children}
+      </main>
+    </div>
+  )
+}