feat: add CLI formatting utilities and table renderer

Implement the presentation layer for terminal output:

- cli/format.go: Human-readable formatting functions — FormatTokens
  (K/M/B suffixes), FormatCost (adaptive precision: $X.XX under $10,
  $X.X under $100, $X over $100, comma-separated over $1000),
  FormatDuration (Xh Ym / Xm / Xs), FormatNumber (comma-separated
  integers), FormatPercent (0-1 -> "XX.X%"), FormatDelta (signed
  cost delta with +/- prefix), FormatDayOfWeek (weekday number to
  3-letter abbreviation).

- cli/render.go: lipgloss-styled output components using the Flexoki
  Dark color palette:

  * RenderTitle: centered title in a rounded border box.

  * RenderTable: full-featured bordered table with auto-calculated
    column widths, right-aligned numeric columns (all except first),
    separator rows (triggered by "---" sentinel), and proper Unicode
    box-drawing characters. Supports optional title header and
    explicit column widths.

  * RenderProgressBar: bracketed fill bar with current/total counts.

  * RenderSparkline: Unicode block sparkline (8-level: ▁ through █)
    from arbitrary float64 series, auto-scaled to max.

  * RenderHorizontalBar: simple horizontal bar chart entry for
    inline comparisons.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/cli/format.go

@@ -0,0 +1,110 @@
+package cli
+
+import (
+	"fmt"
+	"math"
+	"strings"
+)
+
+// FormatTokens formats a token count with human-readable suffixes.
+// e.g., 1234 -> "1.2K", 1234567 -> "1.2M", 1234567890 -> "1.2B"
+func FormatTokens(n int64) string {
+	abs := n
+	if abs < 0 {
+		abs = -abs
+	}
+
+	switch {
+	case abs >= 1_000_000_000:
+		return fmt.Sprintf("%.1fB", float64(n)/1_000_000_000)
+	case abs >= 1_000_000:
+		return fmt.Sprintf("%.1fM", float64(n)/1_000_000)
+	case abs >= 1_000:
+		return fmt.Sprintf("%.1fK", float64(n)/1_000)
+	default:
+		return fmt.Sprintf("%d", n)
+	}
+}
+
+// FormatCost formats a USD cost value.
+func FormatCost(cost float64) string {
+	if cost >= 1000 {
+		return fmt.Sprintf("$%s", FormatNumber(int64(math.Round(cost))))
+	}
+	if cost >= 100 {
+		return fmt.Sprintf("$%.0f", cost)
+	}
+	if cost >= 10 {
+		return fmt.Sprintf("$%.1f", cost)
+	}
+	return fmt.Sprintf("$%.2f", cost)
+}
+
+// FormatDuration formats seconds into a human-readable duration.
+// e.g., 3725 -> "1h 2m", 125 -> "2m", 45 -> "45s"
+func FormatDuration(secs int64) string {
+	if secs <= 0 {
+		return "0s"
+	}
+
+	hours := secs / 3600
+	mins := (secs % 3600) / 60
+
+	if hours > 0 {
+		return fmt.Sprintf("%dh %dm", hours, mins)
+	}
+	if mins > 0 {
+		return fmt.Sprintf("%dm", mins)
+	}
+	return fmt.Sprintf("%ds", secs)
+}
+
+// FormatNumber adds comma separators to an integer.
+// e.g., 1234567 -> "1,234,567"
+func FormatNumber(n int64) string {
+	if n < 0 {
+		return "-" + FormatNumber(-n)
+	}
+
+	s := fmt.Sprintf("%d", n)
+	if len(s) <= 3 {
+		return s
+	}
+
+	var result strings.Builder
+	remainder := len(s) % 3
+	if remainder > 0 {
+		result.WriteString(s[:remainder])
+	}
+	for i := remainder; i < len(s); i += 3 {
+		if result.Len() > 0 {
+			result.WriteByte(',')
+		}
+		result.WriteString(s[i : i+3])
+	}
+	return result.String()
+}
+
+// FormatPercent formats a 0-1 float as a percentage string.
+func FormatPercent(f float64) string {
+	return fmt.Sprintf("%.1f%%", f*100)
+}
+
+// FormatDelta formats a cost delta with sign and color hint.
+// Returns the formatted string and whether it's positive.
+func FormatDelta(current, previous float64) string {
+	delta := current - previous
+	if delta >= 0 {
+		return fmt.Sprintf("+%s", FormatCost(delta))
+	}
+	return fmt.Sprintf("-%s", FormatCost(-delta))
+}
+
+// FormatDayOfWeek returns a 3-letter day abbreviation from a weekday number.
+func FormatDayOfWeek(weekday int) string {
+	days := []string{"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"}
+	if weekday >= 0 && weekday < 7 {
+		return days[weekday]
+	}
+	return "???"
+}

internal/cli/render.go

@@ -0,0 +1,281 @@
+package cli
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/charmbracelet/lipgloss"
+)
+
+// Theme colors (Flexoki Dark)
+var (
+	ColorBg       = lipgloss.Color("#100F0F")
+	ColorSurface  = lipgloss.Color("#1C1B1A")
+	ColorBorder   = lipgloss.Color("#282726")
+	ColorTextDim  = lipgloss.Color("#575653")
+	ColorTextMuted = lipgloss.Color("#6F6E69")
+	ColorText     = lipgloss.Color("#FFFCF0")
+	ColorAccent   = lipgloss.Color("#3AA99F")
+	ColorGreen    = lipgloss.Color("#879A39")
+	ColorOrange   = lipgloss.Color("#DA702C")
+	ColorRed      = lipgloss.Color("#D14D41")
+	ColorBlue     = lipgloss.Color("#4385BE")
+	ColorPurple   = lipgloss.Color("#8B7EC8")
+	ColorYellow   = lipgloss.Color("#D0A215")
+)
+
+// Styles
+var (
+	titleStyle = lipgloss.NewStyle().
+			Bold(true).
+			Foreground(ColorText).
+			Align(lipgloss.Center)
+
+	headerStyle = lipgloss.NewStyle().
+			Bold(true).
+			Foreground(ColorAccent)
+
+	valueStyle = lipgloss.NewStyle().
+			Foreground(ColorText)
+
+	mutedStyle = lipgloss.NewStyle().
+			Foreground(ColorTextMuted)
+
+	costStyle = lipgloss.NewStyle().
+			Foreground(ColorGreen)
+
+	tokenStyle = lipgloss.NewStyle().
+			Foreground(ColorBlue)
+
+	warnStyle = lipgloss.NewStyle().
+			Foreground(ColorOrange)
+
+	dimStyle = lipgloss.NewStyle().
+			Foreground(ColorTextDim)
+)
+
+// Table represents a bordered text table for CLI output.
+type Table struct {
+	Title   string
+	Headers []string
+	Rows    [][]string
+	Widths  []int // optional column widths, auto-calculated if nil
+}
+
+// RenderTitle renders a centered title bar in a bordered box.
+func RenderTitle(title string) string {
+	width := 55
+	border := lipgloss.NewStyle().
+		Border(lipgloss.RoundedBorder()).
+		BorderForeground(ColorBorder).
+		Width(width).
+		Align(lipgloss.Center).
+		Padding(0, 1)
+
+	return border.Render(titleStyle.Render(title))
+}
+
+// RenderTable renders a bordered table with headers and rows.
+func RenderTable(t Table) string {
+	if len(t.Rows) == 0 && len(t.Headers) == 0 {
+		return ""
+	}
+
+	// Calculate column widths
+	numCols := len(t.Headers)
+	if numCols == 0 && len(t.Rows) > 0 {
+		numCols = len(t.Rows[0])
+	}
+
+	widths := make([]int, numCols)
+	if t.Widths != nil {
+		copy(widths, t.Widths)
+	} else {
+		for i, h := range t.Headers {
+			if len(h) > widths[i] {
+				widths[i] = len(h)
+			}
+		}
+		for _, row := range t.Rows {
+			for i, cell := range row {
+				if i < numCols && len(cell) > widths[i] {
+					widths[i] = len(cell)
+				}
+			}
+		}
+	}
+
+	var b strings.Builder
+
+	// Title above table if present
+	if t.Title != "" {
+		b.WriteString("  ")
+		b.WriteString(headerStyle.Render(t.Title))
+		b.WriteString("\n")
+	}
+
+	totalWidth := 1 // left border
+	for _, w := range widths {
+		totalWidth += w + 3 // padding + separator
+	}
+
+	// Top border
+	b.WriteString(dimStyle.Render("╭"))
+	for i, w := range widths {
+		b.WriteString(dimStyle.Render(strings.Repeat("─", w+2)))
+		if i < numCols-1 {
+			b.WriteString(dimStyle.Render("┬"))
+		}
+	}
+	b.WriteString(dimStyle.Render("╮"))
+	b.WriteString("\n")
+
+	// Header row
+	if len(t.Headers) > 0 {
+		b.WriteString(dimStyle.Render("│"))
+		for i, h := range t.Headers {
+			w := widths[i]
+			padded := fmt.Sprintf(" %-*s ", w, h)
+			b.WriteString(headerStyle.Render(padded))
+			if i < numCols-1 {
+				b.WriteString(dimStyle.Render("│"))
+			}
+		}
+		b.WriteString(dimStyle.Render("│"))
+		b.WriteString("\n")
+
+		// Header separator
+		b.WriteString(dimStyle.Render("├"))
+		for i, w := range widths {
+			b.WriteString(dimStyle.Render(strings.Repeat("─", w+2)))
+			if i < numCols-1 {
+				b.WriteString(dimStyle.Render("┼"))
+			}
+		}
+		b.WriteString(dimStyle.Render("┤"))
+		b.WriteString("\n")
+	}
+
+	// Data rows
+	for _, row := range t.Rows {
+		if len(row) == 1 && row[0] == "---" {
+			// Separator row
+			b.WriteString(dimStyle.Render("├"))
+			for i, w := range widths {
+				b.WriteString(dimStyle.Render(strings.Repeat("─", w+2)))
+				if i < numCols-1 {
+					b.WriteString(dimStyle.Render("┼"))
+				}
+			}
+			b.WriteString(dimStyle.Render("┤"))
+			b.WriteString("\n")
+			continue
+		}
+
+		b.WriteString(dimStyle.Render("│"))
+		for i := 0; i < numCols; i++ {
+			w := widths[i]
+			cell := ""
+			if i < len(row) {
+				cell = row[i]
+			}
+
+			// Right-align numeric columns (all except first)
+			var padded string
+			if i == 0 {
+				padded = fmt.Sprintf(" %-*s ", w, cell)
+			} else {
+				padded = fmt.Sprintf(" %*s ", w, cell)
+			}
+			b.WriteString(valueStyle.Render(padded))
+			if i < numCols-1 {
+				b.WriteString(dimStyle.Render("│"))
+			}
+		}
+		b.WriteString(dimStyle.Render("│"))
+		b.WriteString("\n")
+	}
+
+	// Bottom border
+	b.WriteString(dimStyle.Render("╰"))
+	for i, w := range widths {
+		b.WriteString(dimStyle.Render(strings.Repeat("─", w+2)))
+		if i < numCols-1 {
+			b.WriteString(dimStyle.Render("┴"))
+		}
+	}
+	b.WriteString(dimStyle.Render("╯"))
+	b.WriteString("\n")
+
+	return b.String()
+}
+
+// RenderProgressBar renders a simple text progress bar.
+func RenderProgressBar(current, total int, width int) string {
+	if total <= 0 {
+		return ""
+	}
+
+	pct := float64(current) / float64(total)
+	if pct > 1 {
+		pct = 1
+	}
+
+	filled := int(pct * float64(width))
+	if filled > width {
+		filled = width
+	}
+
+	bar := strings.Repeat("█", filled) + strings.Repeat("░", width-filled)
+	return fmt.Sprintf("[%s] %s/%s",
+		mutedStyle.Render(bar),
+		FormatNumber(int64(current)),
+		FormatNumber(int64(total)),
+	)
+}
+
+// RenderSparkline generates a unicode block sparkline from a series of values.
+func RenderSparkline(values []float64) string {
+	if len(values) == 0 {
+		return ""
+	}
+
+	blocks := []rune{'▁', '▂', '▃', '▄', '▅', '▆', '▇', '█'}
+
+	max := values[0]
+	for _, v := range values[1:] {
+		if v > max {
+			max = v
+		}
+	}
+	if max == 0 {
+		max = 1
+	}
+
+	var b strings.Builder
+	for _, v := range values {
+		idx := int(v / max * float64(len(blocks)-1))
+		if idx >= len(blocks) {
+			idx = len(blocks) - 1
+		}
+		if idx < 0 {
+			idx = 0
+		}
+		b.WriteRune(blocks[idx])
+	}
+
+	return b.String()
+}
+
+// RenderHorizontalBar renders a horizontal bar chart entry.
+func RenderHorizontalBar(label string, value, maxValue float64, maxWidth int) string {
+	if maxValue <= 0 {
+		return fmt.Sprintf("  %s", label)
+	}
+	barLen := int(value / maxValue * float64(maxWidth))
+	if barLen < 0 {
+		barLen = 0
+	}
+	bar := strings.Repeat("█", barLen)
+	return fmt.Sprintf("  %s", bar)
+}