feat: private refunds optimizations

noir-projects/noir-contracts/contracts/token_with_refunds_contract/src/main.nr

@@ -463,7 +463,7 @@ contract TokenWithRefunds {
         // 3. Deduct the funded amount from the user's balance - this is a maximum fee a user is willing to pay
         // (called fee limit in aztec spec). The difference between fee limit and the actual tx fee will be refunded 
         // to the user in the `complete_refund(...)` function.
-        storage.balances.sub(user, U128::from_integer(funded_amount)).emit(encode_and_encrypt_note_with_keys(&mut context, user_ovpk, user_ivpk, user));
+        storage.balances.sub(user, U128::from_integer(funded_amount)).emit(encode_and_encrypt_note_with_keys_unconstrained(&mut context, user_ovpk, user_ivpk, user));
 
         // 4. We create the partial notes for the fee payer and the user.
         // --> Called "partial" because they don't have the amount set yet (that will be done in `complete_refund(...)`).