Add arrow key support for folder navigation

Add Left/Right arrow keys as alternatives to h/l for collapsing
and expanding folders in the file panel. Provides more intuitive
navigation for users not familiar with vim keybindings.

- Left arrow: Collapse selected folder (same as 'h')
- Right arrow: Expand selected folder (same as 'l')

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-player"
-version = "0.1.20"
+version = "0.1.21"
 edition = "2021"
 
 [dependencies]

src/main.rs

@@ -626,12 +626,12 @@ async fn handle_key_event<B: ratatui::backend::Backend>(terminal: &mut Terminal<
                 state.move_selection_down();
             }
         }
-        (KeyCode::Char('h'), _) => {
+        (KeyCode::Char('h'), _) | (KeyCode::Left, _) => {
             if !state.focus_playlist {
                 state.collapse_selected();
             }
         }
-        (KeyCode::Char('l'), _) => {
+        (KeyCode::Char('l'), _) | (KeyCode::Right, _) => {
             if !state.focus_playlist {
                 state.expand_selected();
             }