[next] Auth Callback + Chunking (#2139)

* feat: added new auth-callback

* fix: removed unused polyfill code

* fix: fixed missed intersection observer

* feat: enabled vendor chunks

* fix: fix some issues with chunk splitting

* fix: added intersection-observer to app polyfill

* fix: fixed test

* fix: removed lodash plugin which caused issue in prod

* chore: access_token -> accessToken

* feat: Show social login errors

* fix: lint + add test

* fix: restore width after facebook social login

src/core/client/framework/helpers/storageKeys.ts

@@ -0,0 +1 @@
+export const authRedirectBackTo = "authRedirectBackTo";

src/core/client/framework/helpers/urls.tsx

@@ -4,6 +4,7 @@ export default (process.env.NODE_ENV !== "development"
       embed: {
         stream: "/embed/stream",
         auth: "/embed/auth",
+        authCallback: "/embed/auth/callback",
       },
     }
   : {
@@ -11,5 +12,6 @@ export default (process.env.NODE_ENV !== "development"
       embed: {
         stream: "/stream.html",
         auth: "/auth.html",
+        authCallback: "/auth-callback.html",
       },
     });