feat (ee): APIs to configure an auto assignment limit for inboxes (#4672)

Co-authored-by: Pranav Raj S <pranav@chatwoot.com>

app/javascript/shared/mixins/configMixin.js

@@ -9,5 +9,8 @@ export default {
     enabledLanguages() {
       return window.chatwootConfig.enabledLanguages;
     },
+    isEnterprise() {
+      return window.chatwootConfig.isEnterprise === 'true';
+    },
   },
 };