fix(sms): keep charge deposit defaults and unlock referral bonus

Empty SuperAdmin chargeInfo was wiping sms_charge_* on header refresh.
Seed those keys only when empty, and move referral_bonus_amount to can_edit=1.

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

app/Services/SettingsRuntimeCanEditSync.php

@@ -52,6 +52,10 @@ class SettingsRuntimeCanEditSync
         'payping_gateway_name',
         'payping_fin_customer_id',
         'payping_fin_url',
+        'sms_charge_card_number',
+        'sms_charge_sheba',
+        'sms_charge_account_holder',
+        'sms_charge_note',
     ];
 
     /** @return list<string> */