feat: show reply count for each comment in List view

Comments with replies now display a count like "[3 replies]" between
the line number and the resolved status. Uses singular "reply" for
one reply and plural "replies" for multiple.

Author: sideshowbarker

DESIGN.md

@@ -147,11 +147,11 @@ The browse command provides two interactive views:
 ├───────────────────────────────────────────────────────────────────────┤
 │                                                                       │
 │  > src/components/Button.tsx                                          │
-│      @reviewer: Consider using memo here...            (unresolved)   │
-│      @author: Good point, I'll update...               (resolved)     │
+│      @reviewer Line 42 [2 replies]                     (unresolved)   │
+│      @author Line 15                                   (resolved)     │
 │                                                                       │
 │  > src/utils/format.ts                                                │
-│      @reviewer: This could be simplified...            (unresolved)   │
+│      @reviewer Line 8 [1 reply]                        (unresolved)   │
 │                                                                       │
 ├───────────────────────────────────────────────────────────────────────┤
 │  arrows:navigate  enter:view  o:open  r:resolve  Q:quote  a:agent     │

cmd/browse.go

@@ -592,7 +592,18 @@ func (r *browseItemRenderer) Title(item BrowseItem) string {
 	// Comment Metadata
 	style := ui.NewReviewListStyle(item.Comment.Author, item.Comment.IsResolved())
 	// Indent with tree structure
-	return fmt.Sprintf("  └── %s Line %d %s", style.FormatCommentTitle(item.Comment.ID), item.Comment.Line, style.Status.Format(true))
+	title := fmt.Sprintf("  └── %s Line %d", style.FormatCommentTitle(item.Comment.ID), item.Comment.Line)
+	// Add reply count if there are replies
+	if len(item.Comment.ThreadComments) > 0 {
+		replyCount := len(item.Comment.ThreadComments)
+		replyText := "reply"
+		if replyCount > 1 {
+			replyText = "replies"
+		}
+		title += fmt.Sprintf(" [%d %s]", replyCount, replyText)
+	}
+	title += " " + style.Status.Format(true)
+	return title
 }
 
 func (r *browseItemRenderer) Description(item BrowseItem) string {

cmd/browse_test.go

@@ -252,6 +252,72 @@ func TestBuildCommentTree(t *testing.T) {
 	}
 }
 
+func TestBrowseItemRenderer_Title_ReplyCount(t *testing.T) {
+	renderer := &browseItemRenderer{
+		repo:           "owner/repo",
+		prNumber:       123,
+		collapsedFiles: make(map[string]bool),
+	}
+
+	tests := []struct {
+		name           string
+		replyCount     int
+		wantContains   string
+		wantNotContain string
+	}{
+		{
+			name:           "no replies shows no count",
+			replyCount:     0,
+			wantContains:   "",
+			wantNotContain: "repl",
+		},
+		{
+			name:         "one reply shows singular",
+			replyCount:   1,
+			wantContains: "[1 reply]",
+		},
+		{
+			name:         "multiple replies shows plural",
+			replyCount:   3,
+			wantContains: "[3 replies]",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var threadComments []github.ThreadComment
+			for i := 0; i < tt.replyCount; i++ {
+				threadComments = append(threadComments, github.ThreadComment{
+					ID:     int64(100 + i),
+					Author: "replier",
+					Body:   "Reply body",
+				})
+			}
+
+			item := BrowseItem{
+				Type: "comment",
+				Path: "src/main.go",
+				Comment: &github.ReviewComment{
+					ID:             123,
+					Author:         "reviewer",
+					Body:           "Original comment",
+					Line:           42,
+					ThreadComments: threadComments,
+				},
+			}
+
+			title := renderer.Title(item)
+
+			if tt.wantContains != "" && !strings.Contains(title, tt.wantContains) {
+				t.Errorf("Title should contain %q, got: %q", tt.wantContains, title)
+			}
+			if tt.wantNotContain != "" && strings.Contains(title, tt.wantNotContain) {
+				t.Errorf("Title should not contain %q, got: %q", tt.wantNotContain, title)
+			}
+		})
+	}
+}
+
 func TestStripMarkdownForPreview(t *testing.T) {
 	tests := []struct {
 		name     string