fix: auto-submit OTP code on completion in get-started verification step

Add onComplete handler to OtpInput so the verification code auto-submits
when all 6 digits are entered, matching the existing behavior in
LoginOtpStep and OtpStep components.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/portal/src/features/get-started/components/GetStartedForm/steps/VerificationStep.tsx

@@ -24,6 +24,10 @@ export function VerificationStep() {
     setCode(value);
   };
 
+  const handleCodeComplete = (value: string) => {
+    send({ type: "VERIFY_CODE", code: value });
+  };
+
   const handleVerify = () => {
     if (code.length === 6) {
       send({ type: "VERIFY_CODE", code });
@@ -53,6 +57,7 @@ export function VerificationStep() {
       <OtpInput
         value={code}
         onChange={handleCodeChange}
+        onComplete={handleCodeComplete}
         disabled={loading}
         error={error ?? undefined}
         autoFocus