Merge onboarding experiments integration branch (#9571)

* Add onboarding survey page

* Add onboarding new analytics events to mixpanel allowlist

* [web] Try Premium prompt

* moved try-premium code to overleaf-integration

* fixed sheet styling

* Add onboarding flow redirect handling to registration handlers (#9462)

* Add redirect logic for onboarding flow after registration

* Update UPGRADE_PROMPT_URL

* Cleanup style of OverleafAuthenticationController

* Refactor finishLogin calls to call wrapped function in OverleafAuthenticationController

* Refactor user properties/onboarding flow redirect into finishLogin wrapper

* Fix async/await calls after refactoring

* Update tests for finishLogin refactoring

* Don't redirect to upgrade prompt if user has premium via commons

Co-authored-by: Miguel Serrano <mserranom@users.noreply.github.com>
GitOrigin-RevId: 7c392aa6949f99fa909f9ca4e4baad4c4d4ff6be

services/web/app/src/Features/Subscription/SubscriptionController.js

@@ -263,6 +263,8 @@ async function interstitialPaymentPage(req, res) {
   const hasSubscription =
     await LimitationsManager.promises.userHasV1OrV2Subscription(user)
 
+  const showSkipLink = req.query?.skipLink === 'true'
+
   if (hasSubscription) {
     res.redirect('/user/subscription?hasSubscription=true')
   } else {
@@ -272,6 +274,7 @@ async function interstitialPaymentPage(req, res) {
       itm_campaign: req.query?.itm_campaign,
       recommendedCurrency,
       interstitialPaymentConfig,
+      showSkipLink,
     })
   }
 }
@@ -339,6 +342,8 @@ async function successfulSubscription(req, res) {
   const premiumFeaturesDiscoverability =
     premiumFeaturesDiscoverabilityAssignment?.variant === 'active'
 
+  const postCheckoutRedirect = req.session?.postCheckoutRedirect
+
   if (!personalSubscription) {
     res.redirect('/user/subscription/plans')
   } else {
@@ -346,6 +351,7 @@ async function successfulSubscription(req, res) {
       title: 'thank_you',
       personalSubscription,
       premiumFeaturesDiscoverability,
+      postCheckoutRedirect,
     })
   }
 }