This is (or should be) an easy task that's been brought up before and that could improve developer experience without a big bang. I've included a screenshot from how a partner is using the login page's logo as a health check.

Goal is to do a proper jax-rs endpoint, with ModuleManager injected, unlike the current health check: https://git.magnolia-cms.com/projects/OD/repos/cloud-modules/browse/magnolia-now-healthcheck/src/main/java/info/magnolia/cloud/monitoring/healthcheck/servlets/HealthCheckServlet.java