feat: comprehensive seed, Lucide icons, grouped dashboard nav, API fixes

- Rewrite prisma/seed.ts to populate all 27 models with realistic
  Vietnamese real estate data (8 users with login, 10 properties,
  10 listings, orders, payments, reviews, notifications, etc.)
- Replace all emoji icons with Lucide React SVG icons across frontend
  for consistent rendering, sizing, and accessibility
- Redesign dashboard nav: grouped sidebar with section headers,
  primary/secondary split on desktop, icon-only secondary items
- Replace language switcher flag emoji with Globe icon
- Replace SVG theme toggle with Lucide Moon/Sun icons
- Fix API startup: graceful fallback for Sentry profiling, Google OAuth,
  and Zalo OAuth when credentials are not configured
- Relax rate limiting in development mode (10k req/min)
- Fix listings API to include media[] array in search response
- Add optional chaining for property.media across frontend components
- Update OAuth strategy tests to match graceful fallback behavior

Co-Authored-By: Claude Opus 4 (1M context) <noreply@anthropic.com>

apps/web/app/[locale]/(dashboard)/leads/page.tsx

@@ -1,5 +1,6 @@
 'use client';
 
+import { ClipboardList } from 'lucide-react';
 import * as React from 'react';
 import { CreateLeadDialog } from '@/components/leads/create-lead-dialog';
 import { LeadDetailDialog } from '@/components/leads/lead-detail-dialog';
@@ -149,7 +150,7 @@ export default function LeadsPage() {
         </div>
       ) : !result || result.data.length === 0 ? (
         <div className="flex min-h-[300px] flex-col items-center justify-center text-muted-foreground">
-          <p className="text-4xl mb-3">📋</p>
+          <ClipboardList className="h-10 w-10 text-muted-foreground mb-3" aria-hidden="true" />
           <p>Chưa có lead nào</p>
           <Button variant="outline" size="sm" className="mt-3" onClick={() => setCreateOpen(true)}>
             Thêm lead đầu tiên