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

database/factories/CouponFactory.php

@@ -0,0 +1,107 @@
+<?php
+
+namespace Database\Factories;
+
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/**
+ * @extends \Illuminate\Database\Eloquent\Factories\Factory<\App\Models\Coupon>
+ */
+class CouponFactory extends Factory
+{
+    /**
+     * Define the model's default state.
+     *
+     * @return array<string, mixed>
+     */
+    public function definition(): array
+    {
+        $type = fake()->randomElement(['percentage', 'fixed']);
+        $value = $type === 'percentage'
+            ? fake()->numberBetween(5, 50)
+            : fake()->randomFloat(2, 5, 100);
+
+        return [
+            'code' => strtoupper(fake()->lexify('??????')),
+            'name' => fake()->words(3, true),
+            'description' => fake()->sentence(),
+            'type' => $type,
+            'value' => $value,
+            'minimum_amount' => fake()->optional(0.7)->randomFloat(2, 10, 500),
+            'max_uses' => fake()->optional(0.6)->numberBetween(10, 1000),
+            'uses_count' => 0,
+            'max_uses_per_user' => fake()->optional(0.5)->numberBetween(1, 5),
+            'starts_at' => fake()->optional(0.3)->dateTimeBetween('-1 week', 'now'),
+            'expires_at' => fake()->optional(0.8)->dateTimeBetween('now', '+6 months'),
+            'is_active' => true,
+            'metadata' => fake()->optional(0.2)->randomElements([
+                'created_by_admin' => fake()->boolean(),
+                'campaign' => fake()->word(),
+                'region' => fake()->countryCode(),
+            ]),
+        ];
+    }
+
+    /**
+     * Create a percentage-based coupon
+     */
+    public function percentage(): static
+    {
+        return $this->state(fn (array $attributes) => [
+            'type' => 'percentage',
+            'value' => fake()->numberBetween(5, 50),
+        ]);
+    }
+
+    /**
+     * Create a fixed amount coupon
+     */
+    public function fixed(): static
+    {
+        return $this->state(fn (array $attributes) => [
+            'type' => 'fixed',
+            'value' => fake()->randomFloat(2, 5, 100),
+        ]);
+    }
+
+    /**
+     * Create an expired coupon
+     */
+    public function expired(): static
+    {
+        return $this->state(fn (array $attributes) => [
+            'expires_at' => fake()->dateTimeBetween('-1 month', '-1 day'),
+        ]);
+    }
+
+    /**
+     * Create an inactive coupon
+     */
+    public function inactive(): static
+    {
+        return $this->state(fn (array $attributes) => [
+            'is_active' => false,
+        ]);
+    }
+
+    /**
+     * Create a coupon with usage limits
+     */
+    public function withUsageLimit(): static
+    {
+        return $this->state(fn (array $attributes) => [
+            'max_uses' => fake()->numberBetween(10, 100),
+            'max_uses_per_user' => fake()->numberBetween(1, 3),
+        ]);
+    }
+
+    /**
+     * Create a coupon with minimum amount requirement
+     */
+    public function withMinimumAmount(): static
+    {
+        return $this->state(fn (array $attributes) => [
+            'minimum_amount' => fake()->randomFloat(2, 25, 200),
+        ]);
+    }
+}