move to monorepo dir

apps/labrinth/src/routes/not_found.rs

@@ -0,0 +1,11 @@
+use crate::models::error::ApiError;
+use actix_web::{HttpResponse, Responder};
+
+pub async fn not_found() -> impl Responder {
+    let data = ApiError {
+        error: "not_found",
+        description: "the requested route does not exist".to_string(),
+    };
+
+    HttpResponse::NotFound().json(data)
+}