fix(react): Get transferable state in sign in proxy (#7941)

Author: dmoerner

.changeset/nice-jobs-sort.md

@@ -0,0 +1,5 @@
+---
+'@clerk/react': minor
+---
+
+Get transferable state in sign in proxy.

packages/react/src/stateProxy.ts

@@ -142,7 +142,9 @@ export class StateProxy implements State {
       signIn: {
         status: 'needs_identifier' as const,
         availableStrategies: [],
-        isTransferable: false,
+        get isTransferable() {
+          return gateProperty(target, 'isTransferable', false);
+        },
         get id() {
           return gateProperty(target, 'id', undefined);
         },