I have an SPA which is packing into the same jar with backend (spring-boot application). I've added keycloak integration and now frontend redirects users to login page. Backend also needs the issuer url for token verification. Currently keycloak host and port are provided as environment variables during K8S deployment for spring-boot app, but it's unclear to me how to propagate the same variables into frontend. I'm not a frontend developer and couldn't find what is the best practice about sharing a config between front and backend. ChatGPT recommends to expose config endpoint on the backend, but it seems overkill to me, because both are in the same jar. Could you please advise?