fix: the selected row has a background in every pane, not only the focused one

Bold alone was hard to see without a theme, so the other panes didn't
show what was selected in them.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

internal/ui/styles/styles.go

@@ -43,9 +43,11 @@ func Default() Styles {
 		TitleBlurred:  lipgloss.NewStyle(),
 		Footer:        lipgloss.NewStyle().Faint(true),
 
-		// A background rather than reverse, so the row keeps its colours.
+		// A background rather than reverse, so the row keeps its colours;
+		// in every pane, so each shows what's selected in it. The focused
+		// pane's is bold too.
 		Selected:        lipgloss.NewStyle().Background(lipgloss.BrightBlack).Bold(true),
-		SelectedBlurred: lipgloss.NewStyle().Bold(true),
+		SelectedBlurred: lipgloss.NewStyle().Background(lipgloss.BrightBlack),
 		Muted:           lipgloss.NewStyle().Faint(true),
 		Error:           lipgloss.NewStyle().Foreground(lipgloss.Red),
 		Notice:          lipgloss.NewStyle().Foreground(lipgloss.Green),