refactor: extract runtime state backends

apps/aether-gateway/src/router.rs

@@ -9,7 +9,8 @@ use tower::ServiceExt;
 use tower_http::services::{ServeDir, ServeFile};
 use tracing::warn;
 
-use aether_runtime::{prometheus_response, ConcurrencyError, DistributedConcurrencyError};
+use aether_runtime::{prometheus_response, ConcurrencyError};
+use aether_runtime_state::RuntimeSemaphoreError;
 
 use super::{api, handlers::proxy::proxy_request, middleware, state::AppState};
 
@@ -124,7 +125,7 @@ pub(crate) async fn metrics(
 #[derive(Debug)]
 pub(crate) enum RequestAdmissionError {
     Local(ConcurrencyError),
-    Distributed(DistributedConcurrencyError),
+    Distributed(RuntimeSemaphoreError),
 }
 
 pub async fn serve_tcp(bind: &str) -> Result<(), Box<dyn std::error::Error>> {