Function build_router 

pub fn build_router(state: AppState) -> Router

Build the public OCSP router.

When no dedicated admin listener is configured (server.admin_listen unset), the admin API and web UI are nested onto this same router for backward compatibility — the legacy single-port layout. When admin_listen is set, the management surface moves to its own listener (build_admin_router) so it can be given a trusted path (TLS, FTP_TRP.1) without wrapping the plaintext OCSP data plane; this router then serves OCSP only.