fix: sort closed tasks by completion date

internal/db/tasks.go

@@ -145,7 +145,10 @@ func (db *DB) ListTasks(opts ListTasksOptions) ([]*Task, error) {
 		query += " AND status != 'done'"
 	}
 
-	query += " ORDER BY created_at DESC"
+	// Sort done/blocked tasks by completed_at (most recently closed first),
+	// other tasks by created_at (newest first).
+	// Use id DESC as secondary sort for consistent ordering when timestamps are equal.
+	query += " ORDER BY CASE WHEN status IN ('done', 'blocked') THEN completed_at ELSE created_at END DESC, id DESC"
 
 	if opts.Limit > 0 {
 		query += fmt.Sprintf(" LIMIT %d", opts.Limit)

internal/db/tasks_test.go

@@ -496,6 +496,90 @@ func TestLastTaskTypeForProject(t *testing.T) {
 	}
 }
 
+func TestListTasksClosedSortedByCompletedAt(t *testing.T) {
+	// Create temporary database
+	tmpDir := t.TempDir()
+	dbPath := filepath.Join(tmpDir, "test.db")
+
+	database, err := Open(dbPath)
+	if err != nil {
+		t.Fatalf("failed to open database: %v", err)
+	}
+	defer database.Close()
+	defer os.Remove(dbPath)
+
+	// Create tasks in specific order - older tasks first
+	task1 := &Task{
+		Title:   "First task - closed early",
+		Status:  StatusBacklog,
+		Type:    TypeCode,
+		Project: "test",
+	}
+	task2 := &Task{
+		Title:   "Second task - closed late",
+		Status:  StatusBacklog,
+		Type:    TypeCode,
+		Project: "test",
+	}
+	task3 := &Task{
+		Title:   "Third task - not closed",
+		Status:  StatusBacklog,
+		Type:    TypeCode,
+		Project: "test",
+	}
+
+	// Create tasks
+	if err := database.CreateTask(task1); err != nil {
+		t.Fatalf("failed to create task1: %v", err)
+	}
+	if err := database.CreateTask(task2); err != nil {
+		t.Fatalf("failed to create task2: %v", err)
+	}
+	if err := database.CreateTask(task3); err != nil {
+		t.Fatalf("failed to create task3: %v", err)
+	}
+
+	// Close task1 first
+	if err := database.UpdateTaskStatus(task1.ID, StatusDone); err != nil {
+		t.Fatalf("failed to close task1: %v", err)
+	}
+
+	// Then close task2 (so task2 has later completed_at)
+	if err := database.UpdateTaskStatus(task2.ID, StatusDone); err != nil {
+		t.Fatalf("failed to close task2: %v", err)
+	}
+
+	// List all tasks including closed
+	tasks, err := database.ListTasks(ListTasksOptions{IncludeClosed: true})
+	if err != nil {
+		t.Fatalf("failed to list tasks: %v", err)
+	}
+
+	if len(tasks) != 3 {
+		t.Fatalf("expected 3 tasks, got %d", len(tasks))
+	}
+
+	// Find done tasks - the one closed most recently (task2) should appear before task1
+	var doneTasks []*Task
+	for _, task := range tasks {
+		if task.Status == StatusDone {
+			doneTasks = append(doneTasks, task)
+		}
+	}
+
+	if len(doneTasks) != 2 {
+		t.Fatalf("expected 2 done tasks, got %d", len(doneTasks))
+	}
+
+	// task2 (closed later) should be first
+	if doneTasks[0].ID != task2.ID {
+		t.Errorf("expected task2 (most recently closed) to be first, got task%d", doneTasks[0].ID)
+	}
+	if doneTasks[1].ID != task1.ID {
+		t.Errorf("expected task1 (closed earlier) to be second, got task%d", doneTasks[1].ID)
+	}
+}
+
 func TestCreateTaskSavesLastType(t *testing.T) {
 	// Create temporary database
 	tmpDir := t.TempDir()