added settings API + fixed bug (#62)

* added settings API + fixed bug

* removed redundant API funcs

* comment clarifications

---------

Co-authored-by: Wyatt <wyatt@modrinth.com>

theseus_gui/src-tauri/src/main.rs

@@ -38,6 +38,8 @@ fn main() {
             api::auth::auth_has_user,
             api::auth::auth_users,
             api::auth::auth_get_user,
+            api::settings::settings_get,
+            api::settings::settings_set,
         ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");