Replace developer-facing StoreKit error text with user-friendly copy.

Users should see guidance about their internet connection, not Xcode StoreKit configuration details.

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

gramora/Managers/SubscriptionManager.swift

@@ -15,7 +15,7 @@ enum PurchaseError: Equatable {
     var message: String {
         switch self {
         case .productsLoadTimeout:
-            "Couldn't load subscription products right now. Check your StoreKit configuration / internet and try again."
+            "Couldn't load subscription options right now. Check your internet connection and try again."
         case .subscriptionUnavailable:
             "This subscription is currently unavailable. Please try again in a moment."
         case .planUnavailable: