Add POS Pro subscription billing and free-tier limits.

Wallet-backed Pro unlocks unlimited products, restaurant mode, catalog imports, and ecosystem sync features.

Co-authored-by: Cursor <cursoragent@cursor.com>

config/pos.php

@@ -9,4 +9,17 @@ return [
     'kitchen_api_keys' => array_filter([
         'merchant' => env('KITCHEN_API_KEY_MERCHANT'),
     ]),
+
+    'pro' => [
+        'enabled' => filter_var(env('POS_PRO_ENABLED', true), FILTER_VALIDATE_BOOLEAN),
+        'price_minor' => (int) env('POS_PRO_PRICE_MINOR', 7900),
+        'currency' => env('POS_PRO_CURRENCY', 'GHS'),
+        'period_days' => (int) env('POS_PRO_PERIOD_DAYS', 30),
+        'grace_days' => (int) env('POS_PRO_GRACE_DAYS', 3),
+    ],
+
+    'free' => [
+        'max_locations' => (int) env('POS_FREE_MAX_LOCATIONS', 1),
+        'max_products' => (int) env('POS_FREE_MAX_PRODUCTS', 50),
+    ],
 ];