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/logx/log.go

@@ -0,0 +1,59 @@
+package logx
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+func Path() string {
+	return filepath.Join(os.Getenv("HOME"), ".local", "state", "agent-notify", "hook.log")
+}
+
+func Append(format string, args ...any) {
+	path := Path()
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return
+	}
+	f, err := os.OpenFile(path, os.O_CREATE|os.O_APPEND|os.O_WRONLY, 0644)
+	if err != nil {
+		return
+	}
+	defer f.Close()
+	msg := fmt.Sprintf(format, args...)
+	fmt.Fprintf(f, "[%s] %s\n", time.Now().Format(time.RFC3339), msg)
+}
+
+func Tail(n int) ([]string, error) {
+	data, err := os.ReadFile(Path())
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	lines := splitLines(string(data))
+	if n <= 0 || n >= len(lines) {
+		return lines, nil
+	}
+	return lines[len(lines)-n:], nil
+}
+
+func splitLines(s string) []string {
+	var lines []string
+	start := 0
+	for i := 0; i < len(s); i++ {
+		if s[i] == '\n' {
+			line := s[start:i]
+			if line != "" {
+				lines = append(lines, line)
+			}
+			start = i + 1
+		}
+	}
+	if start < len(s) {
+		lines = append(lines, s[start:])
+	}
+	return lines
+}

internal/logx/log_test.go

@@ -0,0 +1,29 @@
+package logx
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestAppendAndTail(t *testing.T) {
+	dir := t.TempDir()
+	t.Setenv("HOME", dir)
+
+	Append("hello %s", "world")
+	lines, err := Tail(10)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(lines) != 1 {
+		t.Fatalf("expected 1 line, got %d", len(lines))
+	}
+	if lines[0] == "" {
+		t.Fatal("empty line")
+	}
+
+	path := filepath.Join(dir, ".local", "state", "agent-notify", "hook.log")
+	if _, err := os.Stat(path); err != nil {
+		t.Fatalf("log file not created: %v", err)
+	}
+}