fix(lifecycle): clean up service subscriptions, proxy retries, and stale runtime state on shutdown

ts/radius/classes.radius.server.ts

@@ -183,6 +183,8 @@ export class RadiusServer {
       this.radiusServer = undefined;
     }
 
+    this.accountingManager.stop();
+
     this.running = false;
     logger.log('info', 'RADIUS server stopped');
   }