feat: admin dashboard UI — DashboardSection as default panel

AdminPanel: Сводка раздел первый (initialSection='dashboard')
DashboardSection: users stats, channels by platform, posts stats,
  revenue vs AI costs cards, drafts pending alert, registrations bar chart 14d
SECTIONS: +Dashboard, +Engine (Движок)
API route: /api/admin/dashboard proxy

app/api/admin/dashboard/route.js

@@ -0,0 +1,15 @@
+import { NextResponse } from 'next/server';
+import { requireUser } from '@/lib/session';
+
+const ENGINE_URL    = process.env.ENGINE_URL    || 'http://127.0.0.1:3030';
+const ENGINE_SECRET = process.env.ENGINE_SECRET || '';
+
+export async function GET() {
+  const user = await requireUser();
+  if (!user?.isAdmin) return NextResponse.json({ error: 'Forbidden' }, { status: 403 });
+  const res = await fetch(`${ENGINE_URL}/api/admin/dashboard`, {
+    headers: { 'x-internal-secret': ENGINE_SECRET, 'x-user-id': String(user.id) },
+    cache: 'no-store',
+  });
+  return NextResponse.json(await res.json());
+}

app/system/page.js

@@ -13,7 +13,7 @@ export default async function SystemPage({ searchParams }) {
   return (
     <>
       <Header user={user} />
-      <AdminPanel initialSection={searchParams?.section || 'settings'} />
+      <AdminPanel initialSection={searchParams?.section || 'dashboard'} />
     </>
   );
 }

components/AdminPanel.js

@@ -8,6 +8,7 @@ import AdminBilling from './admin/AdminBilling';
 // Sidebar navigation
 // ──────────────────────────────────────────────────────────────
 const SECTIONS = [
+  { id: 'dashboard', label: 'Сводка',        icon: BarChart3,  desc: 'Пользователи, посты, финансы' },
   { id: 'settings',  label: 'AI-провайдеры', icon: Settings2,  desc: 'Ключи aiprimetech и routerai' },
   { id: 'engine',    label: 'Движок',         icon: Zap,         desc: 'URL, Telegram, авто-черновики' },
   { id: 'payments',  label: 'ЮKassa',          icon: CreditCard, desc: 'Ключи для приёма оплат' },
@@ -56,6 +57,7 @@ export default function AdminPanel({ initialSection = 'settings' }) {
 
         {/* Content */}
         <div className="flex-1 min-w-0">
+          {section === 'dashboard' && <DashboardSection />}
           {section === 'settings' && <SettingsSection categories={['ai_providers', 'photo_search']} />}
           {section === 'engine'   && <SettingsSection categories={['engine']} />}
           {section === 'payments' && <SettingsSection categories={['payments']} />}
@@ -467,3 +469,144 @@ function PlansSection() {
     </div>
   );
 }
+
+// ──────────────────────────────────────────────────────────────
+// Dashboard section
+// ──────────────────────────────────────────────────────────────
+function DashboardSection() {
+  const [data,    setData]   = useState(null);
+  const [loading, setLoading]= useState(true);
+
+  async function load() {
+    setLoading(true);
+    try {
+      const res = await fetch('/api/admin/dashboard').then(r => r.json());
+      setData(res);
+    } catch {}
+    setLoading(false);
+  }
+
+  if (!data && !loading) load();
+  if (!data && loading) { load(); }
+
+  const PLATFORM_ICONS = { telegram: '✈️', vk: '🔵', max: '🟣' };
+
+  function Stat({ label, value, sub, accent }) {
+    return (
+      <div className={`card p-4 ${accent ? 'border-accent/40 bg-accent/5' : ''}`}>
+        <div className={`text-2xl font-bold ${accent ? 'text-accent' : ''}`}>{value}</div>
+        <div className="text-xs text-gray-400 mt-0.5">{label}</div>
+        {sub && <div className="text-xs text-gray-500 mt-1">{sub}</div>}
+      </div>
+    );
+  }
+
+  return (
+    <div className="space-y-6">
+      <div className="flex items-center justify-between">
+        <h2 className="font-semibold text-lg">Сводка</h2>
+        <button onClick={load} className="btn-ghost p-2"><RefreshCw className="w-4 h-4" /></button>
+      </div>
+
+      {loading && <div className="py-12 text-center"><Loader2 className="w-6 h-6 animate-spin mx-auto text-accent" /></div>}
+
+      {data && (<>
+        {/* Пользователи */}
+        <div>
+          <p className="text-xs text-gray-500 uppercase tracking-wide mb-3">Пользователи</p>
+          <div className="grid grid-cols-3 gap-3">
+            <Stat label="Всего пользователей" value={data.users.total} accent />
+            <Stat label="Новых за 7 дней"     value={data.users.new_7d} />
+            <Stat label="Новых за 30 дней"    value={data.users.new_30d} />
+          </div>
+        </div>
+
+        {/* Каналы */}
+        <div>
+          <p className="text-xs text-gray-500 uppercase tracking-wide mb-3">Каналы</p>
+          <div className="grid grid-cols-4 gap-3">
+            <Stat label="Всего каналов"
+              value={data.channels.reduce((s, c) => s + c.cnt, 0)} />
+            {data.channels.map(c => (
+              <Stat key={c.platform}
+                label={`${PLATFORM_ICONS[c.platform] || '📢'} ${c.platform}`}
+                value={c.cnt} />
+            ))}
+          </div>
+        </div>
+
+        {/* Посты */}
+        <div>
+          <p className="text-xs text-gray-500 uppercase tracking-wide mb-3">Публикации</p>
+          <div className="grid grid-cols-3 gap-3">
+            <Stat label="Всего опубликовано"    value={data.posts.total} />
+            <Stat label="За последние 24 часа"  value={data.posts.today} />
+            <Stat label="За 7 дней"             value={data.posts.week} />
+          </div>
+        </div>
+
+        {/* Финансы */}
+        <div>
+          <p className="text-xs text-gray-500 uppercase tracking-wide mb-3">Финансы</p>
+          <div className="grid grid-cols-2 gap-3">
+            <div className="card p-4 border-green-500/30 bg-green-500/5">
+              <div className="text-2xl font-bold text-green-400">₽{data.revenue.month_rub.toLocaleString('ru-RU')}</div>
+              <div className="text-xs text-gray-400 mt-0.5">Выручка за 30 дней</div>
+              <div className="text-xs text-gray-500 mt-1">{data.revenue.paid_count} платежей • итого ₽{data.revenue.total_rub.toLocaleString('ru-RU')}</div>
+            </div>
+            <div className="card p-4 border-red-500/20 bg-red-500/5">
+              <div className="text-2xl font-bold text-red-400">₽{data.ai.cost_rub.toFixed(2)}</div>
+              <div className="text-xs text-gray-400 mt-0.5">Расходы на AI за 30 дней</div>
+              <div className="text-xs text-gray-500 mt-1">
+                {data.ai.calls} запросов • {data.ai.errors} ошибок
+              </div>
+            </div>
+          </div>
+        </div>
+
+        {/* Черновики */}
+        {data.drafts.pending > 0 && (
+          <div className="card p-4 border-accent/30 bg-accent/5 flex items-center justify-between">
+            <div>
+              <div className="font-medium text-sm">⚡ {data.drafts.pending} черновиков ждут одобрения</div>
+              <div className="text-xs text-gray-400 mt-0.5">Просмотрите и запланируйте публикацию</div>
+            </div>
+            <a href="/drafts" className="btn-primary text-sm px-3 py-1.5">Смотреть →</a>
+          </div>
+        )}
+
+        {/* Регистрации 14 дней */}
+        {data.registrations_14d.length > 0 && (
+          <div>
+            <p className="text-xs text-gray-500 uppercase tracking-wide mb-3">Регистрации — последние 14 дней</p>
+            <div className="card p-4">
+              <div className="flex items-end gap-1 h-16">
+                {(() => {
+                  const max = Math.max(...data.registrations_14d.map(r => r.cnt), 1);
+                  // Заполняем пустые дни
+                  const days = [];
+                  for (let i = 13; i >= 0; i--) {
+                    const d = new Date(); d.setDate(d.getDate() - i);
+                    const key = d.toISOString().split('T')[0];
+                    const found = data.registrations_14d.find(r => r.day === key);
+                    days.push({ day: key, cnt: found?.cnt || 0 });
+                  }
+                  return days.map((r, i) => (
+                    <div key={i} className="flex-1 flex flex-col items-center gap-1">
+                      <div className="w-full bg-accent/20 rounded-sm transition-all"
+                        style={{ height: `${Math.max(2, (r.cnt / max) * 56)}px` }}
+                        title={`${r.day}: ${r.cnt}`} />
+                      {i % 7 === 6 && <div className="text-xs text-gray-600 whitespace-nowrap">
+                        {new Date(r.day).toLocaleDateString('ru-RU', { day: '2-digit', month: 'short' })}
+                      </div>}
+                    </div>
+                  ));
+                })()}
+              </div>
+            </div>
+          </div>
+        )}
+      </>)}
+    </div>
+  );
+}