feat: implement comprehensive multi-provider payment processing system

- Add unified payment provider architecture with contract-based design
  - Implement 6 payment providers: Stripe, Lemon Squeezy, Polar, Oxapay, Crypto, Activation Keys
  - Create subscription management with lifecycle handling (create, cancel, pause, resume, update)
  - Add coupon system with usage tracking and trial extensions
  - Build Filament admin resources for payment providers, subscriptions, coupons, and trials
  - Implement payment orchestration service with provider registry and configuration management
  - Add comprehensive payment logging and webhook handling for all providers
  - Create customer analytics dashboard with revenue, churn, and lifetime value metrics
  - Add subscription migration service for provider switching
  - Include extensive test coverage for all payment functionality

app/Filament/Widgets/RevenueMetrics.php

@@ -0,0 +1,123 @@
+<?php
+
+namespace App\Filament\Widgets;
+
+use App\Models\Subscription;
+use Filament\Widgets\ChartWidget;
+use Illuminate\Support\Facades\DB;
+
+class RevenueMetrics extends ChartWidget
+{
+    protected static ?int $sort = 1;
+
+    protected int|string|array $columnSpan = 'full';
+
+    public function getHeading(): string
+    {
+        return 'Revenue Trends';
+    }
+
+    protected function getData(): array
+    {
+        $monthlyRevenue = $this->getMonthlyRevenueTrend();
+        $mrrByProvider = $this->getMRRByProvider();
+
+        return [
+            'datasets' => [
+                [
+                    'label' => 'Monthly Revenue',
+                    'data' => array_values($monthlyRevenue),
+                    'borderColor' => 'rgba(34, 197, 94, 1)',
+                    'backgroundColor' => 'rgba(34, 197, 94, 0.1)',
+                    'fill' => true,
+                    'tension' => 0.4,
+                ],
+                [
+                    'label' => 'MRR by Provider',
+                    'data' => array_values($mrrByProvider),
+                    'borderColor' => 'rgba(59, 130, 246, 1)',
+                    'backgroundColor' => 'rgba(59, 130, 246, 0.1)',
+                    'fill' => true,
+                    'tension' => 0.4,
+                ],
+            ],
+            'labels' => array_keys($monthlyRevenue),
+        ];
+    }
+
+    protected function getType(): string
+    {
+        return 'line';
+    }
+
+    protected function getOptions(): array
+    {
+        return [
+            'responsive' => true,
+            'interaction' => [
+                'intersect' => false,
+                'mode' => 'index',
+            ],
+            'plugins' => [
+                'legend' => [
+                    'position' => 'top',
+                ],
+                'tooltip' => [
+                    'callbacks' => [
+                        'label' => 'function(context) {
+                            let label = context.dataset.label || "";
+                            if (label) {
+                                label += ": ";
+                            }
+                            if (context.parsed.y !== null) {
+                                label += "$" + context.parsed.y.toFixed(2);
+                            }
+                            return label;
+                        }',
+                    ],
+                ],
+            ],
+            'scales' => [
+                'y' => [
+                    'beginAtZero' => true,
+                    'ticks' => [
+                        'callback' => 'function(value) {
+                            return "$" + value;
+                        }',
+                    ],
+                ],
+            ],
+        ];
+    }
+
+    private function getMonthlyRevenueTrend(): array
+    {
+        return Subscription::query()
+            ->select(
+                DB::raw("strftime('%Y-%m', subscriptions.created_at) as month"),
+                DB::raw('SUM(plans.price) as revenue')
+            )
+            ->join('plans', 'subscriptions.plan_id', '=', 'plans.id')
+            ->where('subscriptions.status', 'active')
+            ->where('subscriptions.created_at', '>=', now()->subMonths(12))
+            ->groupBy('month')
+            ->orderBy('month')
+            ->pluck('revenue', 'month')
+            ->toArray();
+    }
+
+    private function getMRRByProvider(): array
+    {
+        return Subscription::query()
+            ->select(
+                'provider',
+                DB::raw('SUM(plans.price) as mrr')
+            )
+            ->join('plans', 'subscriptions.plan_id', '=', 'plans.id')
+            ->where('subscriptions.status', 'active')
+            ->groupBy('provider')
+            ->orderBy('mrr', 'desc')
+            ->pluck('mrr', 'provider')
+            ->toArray();
+    }
+}