Add onboarding-flow in "register" and "user-registered" events (#15651)

* onboarding-flow in register event

* onboarding-flow in user-registered event

* fix typos

GitOrigin-RevId: aff8a7157062db0ec1c99499353a7c08eaa7b8b6

services/web/app/src/Features/StaticPages/HomeController.js

@@ -67,8 +67,9 @@ module.exports = HomeController = {
 
       return res.render('external/home/v2', {
         designSystemUpdatesVariant: designSystemUpdatesAssignment.variant,
+        onboardingFlowVariant: onboardingFlowAssignment.variant,
         hideNewsletterCheckbox:
-          onboardingFlowAssignment?.variant === 'token-confirmation-odc',
+          onboardingFlowAssignment.variant === 'token-confirmation-odc',
       })
     } else {
       return res.redirect('/login')

services/web/app/src/Features/User/UserCreator.js

@@ -51,10 +51,17 @@ async function recordRegistrationEvent(user) {
     )
   }
 
+  const onboardingFlowAssignment =
+    await SplitTestHandler.promises.getAssignmentForUser(
+      user._id,
+      'onboarding-flow'
+    )
+
   try {
     const segmentation = {
       'home-registration': 'default',
       'split-test-design-system-updates': designSystemUpdatesAssignment.variant,
+      'onboarding-flow': onboardingFlowAssignment.variant,
     }
     if (user.thirdPartyIdentifiers && user.thirdPartyIdentifiers.length > 0) {
       segmentation.provider = user.thirdPartyIdentifiers[0].providerId