added comments to clearify what is in each rust file

src/saveandload.rs

@@ -3,6 +3,12 @@ use serde::{Deserialize, Serialize};
 use std::fs;
 use std::path::PathBuf;
 
+/*
+ * Persistence logic for dungeon state.
+ * Handles saving and loading the complete dungeon state
+ * (settings and layout data) to and from disk using JSON.
+ */
+
 use crate::layout::DungeonLayout;
 use crate::ui::UiSettings;