Central panel SaaS upgrade — Plans/Subscriptions/SuperAdmins/Detail page

Models & migrations:
- subscriptions table (company, plan, period, amount, status, dates, invoice)
- super_admins: role enum (owner/admin/support/sales/finance) + phone + notes
- Subscription model with STATUSES/PERIODS/PAYMENT_METHODS + invoice number
  generator + extends company.active_until on mark_paid
- Company model: subscriptions() + latestSubscription() relations
- SuperAdmin model: role helpers (isOwner, canManageBilling, canManageTenants)

Filament Central panel:
- PlanResource (CRUD, features checklist, limits per plan, abonati count badge)
- SubscriptionResource (CRUD, mark_paid action, navigation badge for overdue)
- SuperAdminResource (CRUD, reset password, toggle 2FA, can't self-delete)
- ViewCompany page with live stats (users/clients/vehicles/WO/parts/revenue/
  storage/last_login + days_until_expiry), subscriptions history table,
  config snapshot, action buttons (open/issue invoice/upload logo/suspend)
- CompanyResource: row click → view, openUrlInNewTab action, recordTitleAttribute,
  empty state, view route registered
- PlatformStats widget upgraded: 6 cards (incl. MRR realized this month, overdue
  invoices count, click-through to filtered tables)
- RevenueChart: 12-month MRR line chart
- RecentTenants: latest 8 tenants with click-through
- PendingPayments: pending+overdue invoices table
- Database notifications enabled + Cmd+K global search
- HEAD_END render hook: PWA manifest + theme color + emoji favicon
- /admin-manifest.json route

Seeder:
- Plans aligned with new FEATURE_OPTIONS (kanban/pdf/reports/ai/api/reverb/etc)
- 4 plans: Free / Basic / Pro / Enterprise (with proper limits)
- SuperAdmin gets role='owner'
- Demo subscription for psauto on Pro plan, marked paid this month

app/Filament/Central/Widgets/PlatformStats.php

@@ -3,6 +3,7 @@
 namespace App\Filament\Central\Widgets;
 
 use App\Models\Central\Company;
+use App\Models\Central\Subscription;
 use Filament\Widgets\StatsOverviewWidget as BaseWidget;
 use Filament\Widgets\StatsOverviewWidget\Stat;
 
@@ -20,20 +21,44 @@ class PlatformStats extends BaseWidget
             ->whereDate('active_until', '<=', now()->addDays(7))
             ->count();
 
+        $mrr = (float) Subscription::where('status', 'paid')
+            ->whereYear('paid_at', date('Y'))
+            ->whereMonth('paid_at', date('m'))
+            ->sum('amount');
+
+        $overdue = Subscription::where('status', 'overdue')->count()
+            + Subscription::where('status', 'pending')
+                ->whereNotNull('due_at')
+                ->where('due_at', '<', now())
+                ->count();
+
         return [
-            Stat::make('Companii total', $total)
-                ->icon('heroicon-o-building-office-2')
-                ->color('primary'),
+            Stat::make('Tenants total', $total)
+                ->description('Toate companiile')
+                ->descriptionIcon('heroicon-m-building-office-2')
+                ->color('primary')
+                ->url(\App\Filament\Central\Resources\CompanyResource::getUrl('index')),
             Stat::make('Active', $active)
-                ->icon('heroicon-o-check-circle')
+                ->description("✓ Pe abonament plătit")
+                ->descriptionIcon('heroicon-m-check-circle')
                 ->color('success'),
-            Stat::make('Trial', $trial)
-                ->icon('heroicon-o-clock')
+            Stat::make('În trial', $trial)
+                ->description($trial > 0 ? 'Posibili clienți noi' : '—')
+                ->descriptionIcon('heroicon-m-clock')
                 ->color('warning'),
-            Stat::make('Expiră în 7 zile', $expiring)
-                ->description($expiring > 0 ? 'Atenție!' : 'Toate ok')
-                ->icon('heroicon-o-exclamation-triangle')
+            Stat::make('Expiră < 7 zile', $expiring)
+                ->description($expiring > 0 ? '⚠ Acțiune necesară' : 'Toate ok')
+                ->descriptionIcon('heroicon-m-exclamation-triangle')
                 ->color($expiring > 0 ? 'danger' : 'success'),
+            Stat::make('Venit luna curentă', number_format($mrr, 0, ',', ' ') . ' MDL')
+                ->description('MRR realizat')
+                ->descriptionIcon('heroicon-m-banknotes')
+                ->color('success'),
+            Stat::make('Facturi neplătite', $overdue)
+                ->description($overdue > 0 ? 'Verifică și amintește' : 'Toate plătite')
+                ->descriptionIcon('heroicon-m-exclamation-circle')
+                ->color($overdue > 0 ? 'danger' : 'gray')
+                ->url(\App\Filament\Central\Resources\SubscriptionResource::getUrl('index') . '?activeTab=overdue'),
         ];
     }
 }