fix(webapp): defer login form validation to submit

Switch conform shouldValidate from onBlur to onSubmit so autofocused
email fields don't flash an error when blurred or on back navigation.

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

Author: samejr

apps/webapp/app/routes/login._index/route.tsx

@@ -172,7 +172,7 @@ export default function LoginPage() {
     onValidate({ formData }) {
       return parseWithZod(formData, { schema: emailSchema });
     },
-    shouldValidate: "onBlur",
+    shouldValidate: "onSubmit",
     shouldRevalidate: "onInput",
   });
 

apps/webapp/app/routes/login.sso/route.tsx

@@ -117,7 +117,7 @@ export default function LoginSsoPage() {
     onValidate({ formData }) {
       return parseWithZod(formData, { schema: ssoEmailSchema });
     },
-    shouldValidate: "onBlur",
+    shouldValidate: "onSubmit",
     shouldRevalidate: "onInput",
   });