feat: fix Cursor hook delivery and improve notify workflow

Route hook notifications through /dev/tty and client_tty so OSC reaches
Ghostty when Cursor captures stdout. Add afterAgentResponse hook, hook
logging, debounce, split test modes, and use directory name for titles.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/hook/debounce.go

@@ -0,0 +1,40 @@
+package hook
+
+import (
+	"os"
+	"path/filepath"
+	"strconv"
+	"time"
+)
+
+func debouncePath() string {
+	return filepath.Join(os.Getenv("HOME"), ".local", "state", "agent-notify", "debounce")
+}
+
+func shouldDebounce(title string) bool {
+	path := debouncePath()
+	data, err := os.ReadFile(path)
+	now := time.Now().UnixNano()
+	window := int64(2 * time.Second)
+
+	var lastTitle string
+	var lastAt int64
+	if err == nil {
+		// format: timestamp\ttitle
+		for i := 0; i < len(data); i++ {
+			if data[i] == '\t' {
+				lastAt, _ = strconv.ParseInt(string(data[:i]), 10, 64)
+				lastTitle = string(data[i+1:])
+				break
+			}
+		}
+	}
+
+	if lastTitle == title && now-lastAt < window {
+		return true
+	}
+
+	_ = os.MkdirAll(filepath.Dir(path), 0755)
+	_ = os.WriteFile(path, []byte(strconv.FormatInt(now, 10)+"\t"+title), 0644)
+	return false
+}