feat: replace spinner with KITT-style red scanning animation

Drop the points spinner and message label in favor of a Knight Rider
scanner that bounces a red glow across 8 small squares. Frames are
pre-rendered with a 3-level intensity trail (#FF0000, #990000, #440000)
at 14 FPS.

Author: ezynda3

cmd/root.go

@@ -876,7 +876,7 @@ func runAgenticStep(ctx context.Context, mcpAgent *agent.Agent, cli *ui.CLI, mes
 
 	// Start initial spinner (skip if quiet)
 	if !config.Quiet && cli != nil {
-		currentSpinner = ui.NewSpinner("Thinking...")
+		currentSpinner = ui.NewSpinner("")
 		currentSpinner.Start()
 	}
 
@@ -1060,7 +1060,7 @@ func runAgenticStep(ctx context.Context, mcpAgent *agent.Agent, cli *ui.CLI, mes
 				responseWasStreamed = false
 				streamingStarted = false
 				// Start spinner again for next LLM call
-				currentSpinner = ui.NewSpinner("Thinking...")
+				currentSpinner = ui.NewSpinner("")
 				currentSpinner.Start()
 			}
 		},
@@ -1086,7 +1086,7 @@ func runAgenticStep(ctx context.Context, mcpAgent *agent.Agent, cli *ui.CLI, mes
 				_ = cli.DisplayAssistantMessageWithModel(content, config.ModelName)
 				lastDisplayedContent = content
 				// Start spinner again for tool calls
-				currentSpinner = ui.NewSpinner("Thinking...")
+				currentSpinner = ui.NewSpinner("")
 				currentSpinner.Start()
 			} else if responseWasStreamed {
 				// Content was already streamed, just track it and manage spinner
@@ -1096,7 +1096,7 @@ func runAgenticStep(ctx context.Context, mcpAgent *agent.Agent, cli *ui.CLI, mes
 					currentSpinner = nil
 				}
 				// Start spinner again for tool calls
-				currentSpinner = ui.NewSpinner("Thinking...")
+				currentSpinner = ui.NewSpinner("")
 				currentSpinner.Start()
 			}
 		},
@@ -1116,7 +1116,7 @@ func runAgenticStep(ctx context.Context, mcpAgent *agent.Agent, cli *ui.CLI, mes
 				return false, err
 			}
 			// Start spinner again for tool calls
-			currentSpinner = ui.NewSpinner("Thinking...")
+			currentSpinner = ui.NewSpinner("")
 			currentSpinner.Start()
 
 			return allow, nil

internal/ui/spinner.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"image/color"
 	"os"
+	"strings"
 	"sync"
 	"time"
 
@@ -12,13 +13,54 @@ import (
 
 // spinnerFrames defines available spinner animation styles.
 var (
-	pointsFrames = []string{"∙∙∙", "●∙∙", "∙●∙", "∙∙●"}
-	pointsFPS    = time.Second / 7
-
 	dotFrames = []string{"⣾ ", "⣽ ", "⣻ ", "⢿ ", "⡿ ", "⣟ ", "⣯ ", "⣷ "}
 	dotFPS    = time.Second / 10
 )
 
+// knightRiderFrames generates a KITT-style scanning animation where a bright
+// red light bounces back and forth across a row of dots with a trailing glow.
+func knightRiderFrames() []string {
+	const numDots = 8
+	const dot = "▪"
+
+	bright := lipgloss.NewStyle().Foreground(lipgloss.Color("#FF0000"))
+	med := lipgloss.NewStyle().Foreground(lipgloss.Color("#990000"))
+	dim := lipgloss.NewStyle().Foreground(lipgloss.Color("#440000"))
+	off := lipgloss.NewStyle().Foreground(lipgloss.Color("#222222"))
+
+	// Scanner bounces: 0→7→0
+	positions := make([]int, 0, 2*numDots-2)
+	for i := 0; i < numDots; i++ {
+		positions = append(positions, i)
+	}
+	for i := numDots - 2; i > 0; i-- {
+		positions = append(positions, i)
+	}
+
+	frames := make([]string, len(positions))
+	for f, pos := range positions {
+		var b strings.Builder
+		for i := 0; i < numDots; i++ {
+			d := pos - i
+			if d < 0 {
+				d = -d
+			}
+			switch {
+			case d == 0:
+				b.WriteString(bright.Render(dot))
+			case d == 1:
+				b.WriteString(med.Render(dot))
+			case d == 2:
+				b.WriteString(dim.Render(dot))
+			default:
+				b.WriteString(off.Render(dot))
+			}
+		}
+		frames[f] = b.String()
+	}
+	return frames
+}
+
 // Spinner provides an animated loading indicator that displays while
 // long-running operations are in progress. It writes directly to stderr
 // using a goroutine-based animation loop, avoiding Bubble Tea's terminal
@@ -27,19 +69,19 @@ type Spinner struct {
 	message string
 	frames  []string
 	fps     time.Duration
-	color   color.Color
+	color   color.Color // nil when frames are pre-rendered with embedded colors
 	done    chan struct{}
 	once    sync.Once
 }
 
 // NewSpinner creates a new animated spinner with the specified message.
-// The spinner uses the theme's primary color and a points animation style.
+// Uses a KITT-style red scanning animation.
 func NewSpinner(message string) *Spinner {
 	return &Spinner{
 		message: message,
-		frames:  pointsFrames,
-		fps:     pointsFPS,
-		color:   GetTheme().Primary,
+		frames:  knightRiderFrames(),
+		fps:     time.Second / 14,
+		color:   nil, // frames are pre-rendered
 		done:    make(chan struct{}),
 	}
 }
@@ -72,14 +114,17 @@ func (s *Spinner) Stop() {
 func (s *Spinner) run() {
 	theme := GetTheme()
 
-	spinnerStyle := lipgloss.NewStyle().
-		Foreground(s.color).
-		Bold(true)
-
 	messageStyle := lipgloss.NewStyle().
 		Foreground(theme.Text).
 		Italic(true)
 
+	var spinnerStyle lipgloss.Style
+	if s.color != nil {
+		spinnerStyle = lipgloss.NewStyle().
+			Foreground(s.color).
+			Bold(true)
+	}
+
 	ticker := time.NewTicker(s.fps)
 	defer ticker.Stop()
 
@@ -92,8 +137,12 @@ func (s *Spinner) run() {
 			return
 		case <-ticker.C:
 			f := s.frames[frame%len(s.frames)]
+			rendered := f
+			if s.color != nil {
+				rendered = spinnerStyle.Render(f)
+			}
 			fmt.Fprintf(os.Stderr, "\r %s %s",
-				spinnerStyle.Render(f),
+				rendered,
 				messageStyle.Render(s.message))
 			frame++
 		}