feat(tui): ntcharts latency line chart in inline detail panel

Replace block-element sparkline with ntcharts streamline chart in the
inline detail panel. Renders a 4-row line chart with thin line style
using the theme accent color. Auto-scales Y axis to latency range.

Added github.com/NimbleMarkets/ntcharts v0.5.1 dependency (lipgloss v1
compatible). Min/Avg/Max stats rendered below the chart.

internal/tui/chart.go

@@ -0,0 +1,31 @@
+package tui
+
+import (
+	"time"
+
+	"github.com/NimbleMarkets/ntcharts/canvas/runes"
+	"github.com/NimbleMarkets/ntcharts/linechart/streamlinechart"
+	"github.com/charmbracelet/lipgloss"
+)
+
+func (m Model) latencyChart(latencies []time.Duration, statuses []bool, width, height int) string {
+	if len(latencies) == 0 || width < 10 || height < 3 {
+		return ""
+	}
+
+	lineStyle := lipgloss.NewStyle().Foreground(m.theme.Accent)
+	slc := streamlinechart.New(width, height,
+		streamlinechart.WithStyles(runes.ThinLineStyle, lineStyle),
+	)
+
+	for i, l := range latencies {
+		ms := float64(l.Milliseconds())
+		if i < len(statuses) && !statuses[i] {
+			ms = 0
+		}
+		slc.Push(ms)
+	}
+	slc.Draw()
+
+	return slc.View()
+}

internal/tui/update.go

@@ -142,7 +142,7 @@ func (m *Model) handleFormMsg(msg tea.Msg) (tea.Model, tea.Cmd) {
 	return m, nil
 }
 
-const detailInlineHeight = 8
+const detailInlineHeight = 12
 
 func (m *Model) recalcLayout() {
 	chrome := chromeBase

internal/tui/view_detail_inline.go

@@ -67,14 +67,16 @@ func (m Model) viewDetailInline(width int) string {
 	}
 
 	if len(hist.Latencies) > 0 {
-		sparkW := width - 30
-		if sparkW < 10 {
-			sparkW = 10
+		chartW := width - 4
+		if chartW < 20 {
+			chartW = 20
 		}
-		if sparkW > detailSparkWidth {
-			sparkW = detailSparkWidth
+		chartH := 4
+		chart := m.latencyChart(hist.Latencies, hist.Statuses, chartW, chartH)
+		if chart != "" {
+			b.WriteString(chart + "\n")
 		}
-		spark := m.latencySparkline(hist.Latencies, hist.Statuses, sparkW, m.theme.Bg)
+
 		minMs := hist.Latencies[0].Milliseconds()
 		maxMs := hist.Latencies[0].Milliseconds()
 		var sumMs int64
@@ -89,11 +91,11 @@ func (m Model) viewDetailInline(width int) string {
 			sumMs += ms
 		}
 		avgMs := sumMs / int64(len(hist.Latencies))
-		stats := fmt.Sprintf("Min %s  Avg %s  Max %s",
+		stats := fmt.Sprintf("  Min %s  Avg %s  Max %s",
 			m.fmtLatency(time.Duration(minMs)*time.Millisecond),
 			m.fmtLatency(time.Duration(avgMs)*time.Millisecond),
 			m.fmtLatency(time.Duration(maxMs)*time.Millisecond))
-		b.WriteString("  " + spark + "  " + stats + "\n")
+		b.WriteString(stats + "\n")
 	}
 
 	keys := m.st.subtleStyle.Render("[h] History  [s] SLA  [e] Edit  [esc] Close")