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

tests/Feature/PaymentProviderControllerTest.php

@@ -0,0 +1,147 @@
+<?php
+
+use App\Models\ActivationKey;
+use App\Models\User;
+use App\Services\Payments\PaymentConfigurationManager;
+use App\Services\Payments\PaymentOrchestrator;
+use App\Services\Payments\ProviderRegistry;
+
+test('can redeem activation key', function () {
+    $user = User::factory()->create();
+
+    // Create an activation key
+    $activationKey = ActivationKey::factory()->create([
+        'activation_key' => 'TEST-KEY-123',
+        'is_activated' => false,
+    ]);
+
+    $response = actingAs($user)
+        ->postJson('/api/activation-keys/redeem', [
+            'activation_key' => 'TEST-KEY-123',
+        ]);
+
+    expect($response->status())->toBe(200);
+    $data = $response->json();
+    expect($data['success'])->toBeTrue();
+    expect($data['data'])->toHaveKey('subscription_id');
+
+    // Verify the key is now activated
+    $activationKey->refresh();
+    expect($activationKey->is_activated)->toBeTrue();
+});
+
+test('requires authentication to redeem activation key', function () {
+    $response = postJson('/api/activation-keys/redeem', [
+        'activation_key' => 'TEST-KEY-123',
+    ]);
+
+    expect($response->status())->toBe(401);
+});
+
+test('can validate activation key', function () {
+    // Create an activation key
+    $activationKey = ActivationKey::factory()->create([
+        'activation_key' => 'VALIDATE-KEY-123',
+        'is_activated' => false,
+    ]);
+
+    $response = getJson('/api/activation-keys/validate/VALIDATE-KEY-123');
+
+    expect($response->status())->toBe(200);
+    $data = $response->json();
+    expect($data['valid'])->toBeTrue();
+    expect($data['is_activated'])->toBeFalse();
+});
+
+test('returns invalid for non-existent activation key', function () {
+    $response = getJson('/api/activation-keys/validate/NON-EXISTENT');
+
+    expect($response->status())->toBe(200);
+    $data = $response->json();
+    expect($data['valid'])->toBeFalse();
+    expect($data['reason'])->toBe('Activation key not found');
+});
+
+test('can get crypto exchange rate', function () {
+    $response = getJson('/api/crypto/rates/btc');
+
+    expect($response->status())->toBe(200);
+    $response->assertJsonStructure([
+        'crypto',
+        'rate_usd_per_crypto',
+        'rate_crypto_per_usd',
+        'updated_at',
+    ]);
+
+    $data = $response->json();
+    expect($data['crypto'])->toBe('BTC');
+    expect($data['rate_usd_per_crypto'])->toBeNumeric();
+    expect($data['rate_crypto_per_usd'])->toBeNumeric();
+});
+
+test('can convert usd to crypto', function () {
+    $response = getJson('/api/crypto/convert?usd_amount=100&crypto=btc');
+
+    expect($response->status())->toBe(200);
+    $response->assertJsonStructure([
+        'usd_amount',
+        'crypto',
+        'crypto_amount',
+        'fees',
+        'net_crypto_amount',
+        'updated_at',
+    ]);
+
+    $data = $response->json();
+    expect($data['usd_amount'])->toBe(100.0);
+    expect($data['crypto'])->toBe('BTC');
+    expect($data['crypto_amount'])->toBeNumeric();
+    expect($data['fees'])->toHaveKey('total_fee');
+});
+
+test('validates crypto conversion parameters', function () {
+    // Invalid crypto type
+    $response = getJson('/api/crypto/convert?usd_amount=100&crypto=invalid');
+
+    expect($response->status())->toBe(422);
+
+    // Invalid amount
+    $response = getJson('/api/crypto/convert?usd_amount=0&crypto=btc');
+
+    expect($response->status())->toBe(422);
+});
+
+test('payment routes exist', function () {
+    // Test that basic payment routes exist
+    $response = getJson('/api/payment/success');
+    expect($response->status())->toBe(200);
+
+    $response = getJson('/api/payment/cancel');
+    expect($response->status())->toBe(200);
+});
+
+test('can create simple provider registry', function () {
+    $registry = new ProviderRegistry;
+    expect($registry)->toBeInstanceOf(ProviderRegistry::class);
+    expect($registry->getAllProviders())->toHaveCount(0);
+});
+
+test('can create configuration manager', function () {
+    $registry = new ProviderRegistry;
+    $configManager = new PaymentConfigurationManager($registry);
+
+    expect($configManager)->toBeInstanceOf(PaymentConfigurationManager::class);
+
+    // Test that activation key is always available
+    $configManager->initializeProviders();
+    expect($registry->has('activation_key'))->toBeTrue();
+});
+
+test('can create payment orchestrator', function () {
+    $registry = new ProviderRegistry;
+    $configManager = new PaymentConfigurationManager($registry);
+    $orchestrator = new PaymentOrchestrator($registry, $configManager);
+
+    expect($orchestrator)->toBeInstanceOf(PaymentOrchestrator::class);
+    expect($orchestrator->getRegistry())->toBe($registry);
+});