Use lowercase for panel labels

Change "Files" to "files" and "Playlist" to "playlist" in the title bar
for consistent lowercase styling. Also remove unused render_info_popup
function.

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cm-player"
-version = "0.1.36"
+version = "0.1.37"
 edition = "2021"
 
 [dependencies]

src/ui/mod.rs

@@ -46,13 +46,13 @@ pub fn render(frame: &mut Frame, state: &mut AppState, player: &mut Player) -> (
 
     // Add playlist counter
     let playlist_text = if !state.playlist.is_empty() {
-        format!("Playlist [{}/{}]", state.playlist_index + 1, state.playlist.len())
+        format!("playlist [{}/{}]", state.playlist_index + 1, state.playlist.len())
     } else {
-        "Playlist (empty)".to_string()
+        "playlist (empty)".to_string()
     };
 
     let title = Line::from(vec![
-        Span::styled("Files", file_style),
+        Span::styled("files", file_style),
         Span::raw(" | "),
         Span::styled(playlist_text, playlist_style),
     ]);
@@ -719,42 +719,6 @@ fn render_progress_bar(frame: &mut Frame, _state: &AppState, player: &mut Player
     frame.render_widget(progress_widget, area);
 }
 
-fn render_info_popup(frame: &mut Frame, message: &str) {
-    // Create centered popup area - smaller than confirm popup
-    let area = frame.area();
-    let popup_width = 40;
-    let popup_height = 3;
-
-    let popup_area = Rect {
-        x: (area.width.saturating_sub(popup_width)) / 2,
-        y: (area.height.saturating_sub(popup_height)) / 2,
-        width: popup_width.min(area.width),
-        height: popup_height.min(area.height),
-    };
-
-    // Use Clear widget to completely erase the background
-    frame.render_widget(Clear, popup_area);
-
-    // Render the popup block with solid background
-    let block = Block::default()
-        .borders(Borders::ALL)
-        .style(Style::default()
-            .bg(Theme::background())
-            .fg(Theme::bright_foreground()));
-
-    let inner = block.inner(popup_area);
-    frame.render_widget(block, popup_area);
-
-    // Render message centered
-    let message_widget = Paragraph::new(message)
-        .alignment(Alignment::Center)
-        .style(Style::default()
-            .fg(Theme::bright_foreground())
-            .bg(Theme::background()));
-
-    frame.render_widget(message_widget, inner);
-}
-
 fn render_refresh_popup(frame: &mut Frame, file_count: usize) {
     // Create centered popup area - bigger for two lines
     let area = frame.area();