style: move structs to objects and split into several files for readability

src/api/v1/guilds/uuid/roles/uuid.rs

@@ -2,7 +2,7 @@ use crate::{
     Data,
     api::v1::auth::check_access_token,
     error::Error,
-    structs::{Member, Role},
+    objects::{Member, Role},
     utils::{get_auth_header, global_checks},
 };
 use ::uuid::Uuid;