feat: Update default credit add amount from $5 to $10 (#5463)

Updated the PaymentModal component to change the default credit add
amount from $5 to $10. This includes:
- Changed initial amount state from 5 to 10
- Updated preset amounts array to start with $10 instead of $5
- Updated MIN_AMOUNT constant from 5 to 10
- Updated default reset amount from 5 to 10

Fixes ENG-3820

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Co-authored-by: replicas-connector[bot] <replicas-connector[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

Author: replicas-connector[bot]

web/components/templates/settings/PaymentModal.tsx

@@ -20,13 +20,13 @@ const PaymentModal: React.FC<PaymentModalProps> = ({
   onClose,
   returnUrl,
 }) => {
-  const [amount, setAmount] = useState(5);
+  const [amount, setAmount] = useState(10);
   const [customAmount, setCustomAmount] = useState("");
   const createCheckoutSession = useCreateCheckoutSession();
   const { setNotification } = useNotification();
 
-  const presetAmounts = [5, 20, 100, 500];
-  const MIN_AMOUNT = 5;
+  const presetAmounts = [10, 20, 100, 500];
+  const MIN_AMOUNT = 10;
 
   const creditsAmountCents = Math.round(amount * 100);
   const percentageFeeCents = Math.ceil(
@@ -47,7 +47,7 @@ const PaymentModal: React.FC<PaymentModalProps> = ({
     setCustomAmount(value);
 
     if (value === "") {
-      setAmount(5);
+      setAmount(10);
       return;
     }