feat(presentation): GET /health endpoint

crates/presentation/src/routes.rs

@@ -16,6 +16,8 @@ use crate::{handlers::*, state::AppState};
 
 pub fn router(fed_config: &ApFederationConfig) -> Router<AppState> {
     let api_routes = Router::new()
+        // health
+        .route("/health", get(health::health_handler))
         // auth
         .route("/auth/register", post(auth::post_register))
         .route("/auth/login", post(auth::post_login))