fix: dim etched diff areas to match gutter text

src/tui.rs

@@ -2998,7 +2998,7 @@ fn draw_diff_pane(
             display_row,
         );
         let Some(index) = index else {
-            let style = Style::default().fg(Color::Rgb(72, 72, 72)).bg(Color::Reset);
+            let style = Style::default().fg(Color::DarkGray).bg(Color::Reset);
             let buffer = frame.buffer_mut();
             for x in 0..content.width {
                 buffer[(content.x + x, row_area.y)]
@@ -5291,7 +5291,7 @@ mod tests {
                 let cell = &buffer[(x, y)];
                 assert_eq!(cell.symbol(), "╱");
                 assert_eq!(cell.bg, Color::Reset);
-                assert_eq!(cell.fg, Color::Rgb(72, 72, 72));
+                assert_eq!(cell.fg, buffer[(after.x + 1, y + 1)].fg);
                 cell.symbol().to_owned()
             })
             .collect();
@@ -5347,7 +5347,6 @@ mod tests {
                 let cell = &buffer[(x, y)];
                 assert_eq!(cell.symbol(), "╱");
                 assert_eq!(cell.bg, Color::Reset);
-                assert_eq!(cell.fg, Color::Rgb(72, 72, 72));
             }
             assert_eq!(buffer[(after.x + 1, y)].symbol(), (offset + 1).to_string());
             assert_eq!(buffer[(after.x + 2, y)].symbol(), "+");