server : include total "num_slots" in props endpoint (ggerganov#5349)

examples/server/server.cpp

@@ -432,6 +432,7 @@ struct llama_server_context
         }
 
         default_generation_settings_for_props = get_formated_generation(slots.front());
+        default_generation_settings_for_props["num_slots"] = params.n_parallel;
         default_generation_settings_for_props["seed"] = -1;
 
         batch = llama_batch_init(n_ctx, 0, params.n_parallel);