Move result structures to a more appropriate location

rust/sea_battle_backend/src/utils/mod.rs

@@ -1,13 +1,4 @@
-use std::error::Error;
-use std::fmt::Display;
-use std::io::ErrorKind;
-
 pub mod network_utils;
+pub mod res_utils;
 pub mod string_utils;
 pub mod time_utils;
-
-pub type Res<E = ()> = Result<E, Box<dyn Error>>;
-
-pub fn boxed_error<D: Display>(msg: D) -> Box<dyn Error> {
-    Box::new(std::io::Error::new(ErrorKind::Other, msg.to_string()))
-}

rust/sea_battle_backend/src/utils/res_utils.rs

@@ -0,0 +1,9 @@
+use std::error::Error;
+use std::fmt::Display;
+use std::io::ErrorKind;
+
+pub type Res<E = ()> = Result<E, Box<dyn Error>>;
+
+pub fn boxed_error<D: Display>(msg: D) -> Box<dyn Error> {
+    Box::new(std::io::Error::new(ErrorKind::Other, msg.to_string()))
+}