feat(tui): improve scrollbar visibility and extend to all panels

Use block characters (█/░) with accent coloring for scrollbar thumb/track
instead of box-drawing chars that blend with panel borders. Auto-derive
scrollbar from content overflow in titledPanelH. Add scrollbar to logs
and maintenance bottom panels.

internal/tui/panel.go

@@ -70,6 +70,9 @@ func (m Model) titledPanelH(title, content, footer string, width, height, scroll
 	}
 	visible := contentLines[scrollOffset:end]
 
+	if sb.total == 0 && len(contentLines) > bodyH {
+		sb = scrollbar{pos: scrollOffset, total: len(contentLines), visible: bodyH}
+	}
 	sbVisible := sb.visible
 	if sbVisible <= 0 {
 		sbVisible = bodyH
@@ -96,8 +99,8 @@ func (m Model) titledPanelH(title, content, footer string, width, height, scroll
 		}
 	}
 
-	scrollTrack := bc.Render("│")
+	scrollTrack := lipgloss.NewStyle().Foreground(m.theme.Border).Render("░")
-	scrollThumb := lipgloss.NewStyle().Foreground(m.theme.Muted).Render("┃")
+	scrollThumb := lipgloss.NewStyle().Foreground(m.theme.Accent).Render("█")
 
 	borderLine := func(line string, idx int) string {
 		rightBorder := bc.Render("│")

internal/tui/tab_logs_sidebar.go

@@ -72,6 +72,20 @@ func (m Model) viewLogsStrip(width, maxLines int) string {
 	return style.Render(strings.Join(visible, "\n"))
 }
 
+func (m Model) filteredLogCount() int {
+	count := 0
+	for _, entry := range m.engine.GetLogs() {
+		if strings.TrimSpace(entry.Message) == "" {
+			continue
+		}
+		if m.logFilterImportant && !isImportantLog(classifyLog(entry.Message)) {
+			continue
+		}
+		count++
+	}
+	return count
+}
+
 func (m *Model) scrollLogs(delta int) {
 	logs := m.engine.GetLogs()
 	total := 0

internal/tui/view_dashboard.go

@@ -189,12 +189,16 @@ func (m Model) viewMonitorsLayout() string {
 
 	switch m.bottomPanel {
 	case bottomLogs:
-		logContent := m.viewLogsStrip(availW-2, logsStripHeight-2)
+		maxLines := logsStripHeight - 2
-		logPanel := m.zones.Mark("panel-logs", m.titledPanel("Logs", logContent, availW, m.focusedPanel == panelLogs))
+		logContent := m.viewLogsStrip(availW-2, maxLines)
+		totalLogs := m.filteredLogCount()
+		logPanel := m.zones.Mark("panel-logs", m.titledPanelH("Logs", logContent, "", availW, logsStripHeight, 0, scrollbar{pos: m.logScrollOffset, total: totalLogs, visible: maxLines}, m.focusedPanel == panelLogs))
 		return top + "\n" + logPanel
 	case bottomMaint:
-		maintContent := m.viewMaintStrip(availW-2, logsStripHeight-2)
+		maxLines := logsStripHeight - 2
-		maintPanel := m.zones.Mark("panel-maint", m.titledPanel("Maint", maintContent, availW, m.focusedPanel == panelMaint))
+		maintContent := m.viewMaintStrip(availW-2, maxLines)
+		totalMaint := len(m.activeMaintWindows())
+		maintPanel := m.zones.Mark("panel-maint", m.titledPanelH("Maint", maintContent, "", availW, logsStripHeight, 0, scrollbar{pos: 0, total: totalMaint, visible: maxLines}, m.focusedPanel == panelMaint))
 		return top + "\n" + maintPanel
 	}
 	return top