fix: show context window percentage in statusbar

- Replace meaningless token count (@721) with ctx: N%
- Color-code: muted <75%, amber 75-89%, red 90%+
- Fix integer division rounding to zero for small percentages
- Remove SetContextCount, keep only SetContextPercent
- Toast always reserves 1 line to prevent layout shifts
- Remove gapBeforeToast padding

Author: binarylogic

internal/app/app.go

@@ -48,7 +48,6 @@ const (
 	horizontalPadding = 1
 	verticalPadding   = 1
 	gapAfterStatusBar = 1
-	gapBeforeToast    = 1
 
 	minWidth  = 50
 	minHeight = 25
@@ -233,11 +232,9 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			}()
 		}
 		// Update context window usage in statusbar
-		if msg.InputTokens > 0 {
-			m.statusBar.SetContextCount(msg.InputTokens + msg.OutputTokens)
-		}
 		if msg.InputTokens > 0 && msg.ContextWindow > 0 {
-			m.statusBar.SetContextPercent(msg.InputTokens * 100 / msg.ContextWindow)
+			pct := (msg.InputTokens*100 + msg.ContextWindow - 1) / msg.ContextWindow // round up
+			m.statusBar.SetContextPercent(pct)
 		}
 	}
 
@@ -285,10 +282,8 @@ func (m *Model) updateLayout() {
 	keyBarHeight := m.keyBar.Height()
 
 	// Page is flexible - gets remaining height
-	pageHeight := contentHeight - statusBarHeight - gapAfterStatusBar - keyBarHeight
-	if toastHeight > 0 {
-		pageHeight -= toastHeight + gapBeforeToast
-	}
+	// Toast always reserves its line to prevent layout shifts
+	pageHeight := contentHeight - statusBarHeight - gapAfterStatusBar - toastHeight - keyBarHeight
 
 	switch m.state {
 	case stateOnboarding:
@@ -450,10 +445,8 @@ func (m *Model) renderContent() string {
 	}
 
 	// Calculate page height (flexible component gets remaining space)
-	pageHeight := contentHeight - statusBarHeight - gapAfterStatusBar - keyBarHeight
-	if toastHeight > 0 {
-		pageHeight -= toastHeight + gapBeforeToast
-	}
+	// Toast always reserves its line to prevent layout shifts
+	pageHeight := contentHeight - statusBarHeight - gapAfterStatusBar - toastHeight - keyBarHeight
 
 	// Style page to fill its allocated space
 	styledPage := lipgloss.NewStyle().
@@ -467,10 +460,7 @@ func (m *Model) renderContent() string {
 	sections = append(sections, statusBarView)
 	sections = append(sections, "") // gapAfterStatusBar
 	sections = append(sections, styledPage)
-	if toastHeight > 0 {
-		sections = append(sections, "") // gapBeforeToast
-		sections = append(sections, toastView)
-	}
+	sections = append(sections, toastView)
 	if keyBarHeight > 0 {
 		sections = append(sections, keyBarView)
 	}

internal/app/statusbar/statusbar.go

@@ -3,6 +3,7 @@ package statusbar
 
 import (
 	"fmt"
+	"image/color"
 	"strings"
 
 	tea "charm.land/bubbletea/v2"
@@ -31,9 +32,6 @@ type Model struct {
 	// Conversation
 	title string
 
-	// Context
-	contextCount int
-
 	// Context window usage (0-100)
 	contextPercent int
 }
@@ -88,11 +86,6 @@ func (m *Model) SetTitle(title string) {
 	m.title = title
 }
 
-// SetContextCount sets the number of entities in context.
-func (m *Model) SetContextCount(count int) {
-	m.contextCount = count
-}
-
 // SetContextPercent sets the context window usage percentage.
 func (m *Model) SetContextPercent(percent int) {
 	m.contextPercent = percent
@@ -112,7 +105,6 @@ func (m *Model) View() string {
 	colors := m.theme.Colors
 	diagStyle := lipgloss.NewStyle().Foreground(colors.Brand.GradientEnd)
 	sepStyle := lipgloss.NewStyle().Foreground(colors.Page.TextMuted)
-	mutedStyle := lipgloss.NewStyle().Foreground(colors.Page.TextMuted)
 
 	sep := sepStyle.Render(" │ ")
 
@@ -150,18 +142,9 @@ func (m *Model) View() string {
 		}
 	}
 
-	// 5. Context count (if fits)
-	if m.contextCount > 0 {
-		ctxSeg := mutedStyle.Render(fmt.Sprintf("@%d", m.contextCount))
-		testContent := strings.Join(segments, sep) + sep + ctxSeg
-		if lipgloss.Width(testContent) < m.width-8 {
-			segments = append(segments, ctxSeg)
-		}
-	}
-
-	// 6. Context percent (if fits)
+	// 5. Context window usage (if fits)
 	if m.contextPercent > 0 {
-		pctSeg := mutedStyle.Render(fmt.Sprintf("%d%%", m.contextPercent))
+		pctSeg := m.renderContextPercent()
 		testContent := strings.Join(segments, sep) + sep + pctSeg
 		if lipgloss.Width(testContent) < m.width-3 {
 			segments = append(segments, pctSeg)
@@ -224,3 +207,21 @@ func (m *Model) renderTitle(maxWidth int) string {
 
 	return style.Render("\"" + title + "\"")
 }
+
+// renderContextPercent renders "ctx: N%" with color based on usage level.
+func (m *Model) renderContextPercent() string {
+	colors := m.theme.Colors
+
+	var fg color.Color
+	switch {
+	case m.contextPercent >= 90:
+		fg = colors.Error.Fg
+	case m.contextPercent >= 75:
+		fg = colors.Warning.Fg
+	default:
+		fg = colors.Page.TextMuted
+	}
+
+	style := lipgloss.NewStyle().Foreground(fg)
+	return style.Render(fmt.Sprintf("ctx: %d%%", m.contextPercent))
+}

internal/app/toast/toast.go

@@ -56,11 +56,8 @@ func (m *Model) SetWidth(width int) {
 }
 
 // Height returns the number of lines this component renders.
-// Returns 0 when no toast is showing, 1 when a toast is visible.
+// Always returns 1 to reserve space and prevent layout shifts.
 func (m *Model) Height() int {
-	if m.current == nil {
-		return 0
-	}
 	return 1
 }
 
@@ -91,10 +88,10 @@ func (m *Model) show(t toast) tea.Cmd {
 	return clearAfter(DefaultTTL)
 }
 
-// View renders the toast. Returns empty string if no toast.
+// View renders the toast. Returns an empty line if no toast to reserve space.
 func (m *Model) View() string {
 	if m.current == nil {
-		return ""
+		return " "
 	}
 
 	colors := m.theme.Colors