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

routes/web.php

@@ -47,6 +47,25 @@ Route::post('/locale/{lang}', function (Request $request, string $lang) {
     return back();
 })->name('locale.switch');
 
+// PWA — manifest pentru panou central (service.mir.md).
+Route::get('/admin-manifest.json', function () {
+    return response()->json([
+        'name' => 'AutoCRM Admin',
+        'short_name' => 'AutoCRM',
+        'description' => 'Panou administrativ AutoCRM SaaS',
+        'start_url' => '/admin',
+        'display' => 'standalone',
+        'orientation' => 'any',
+        'background_color' => '#ffffff',
+        'theme_color' => '#6366f1',
+        'lang' => 'ro',
+        'icons' => [
+            ['src' => '/pwa/admin-192.png', 'sizes' => '192x192', 'type' => 'image/png'],
+            ['src' => '/pwa/admin-512.png', 'sizes' => '512x512', 'type' => 'image/png'],
+        ],
+    ])->header('Cache-Control', 'public, max-age=3600');
+});
+
 // PWA — manifest dinamic per tenant.
 Route::get('/manifest.json', function (Request $request) {
     $tenant = app(TenantManager::class)->current();