feat: implement agent-notify CLI with hooks and tmux passthrough

Add OSC 777 notification sender, Cursor/Claude hook adapters,
config/install commands, and README for Ghostty + tmux setup.

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

internal/install/install.go

@@ -0,0 +1,104 @@
+package install
+
+import (
+	"encoding/json"
+	"os"
+	"path/filepath"
+
+	"github.com/longbin/agent-notify/internal/config"
+)
+
+const cursorHookCmd = "agent-notify hook cursor stop"
+const cursorToolCmd = "agent-notify hook cursor tool"
+const claudeStopCmd = "agent-notify hook claude stop"
+const claudeIdleCmd = "agent-notify hook claude idle"
+
+func CursorHooksPath() string {
+	return filepath.Join(os.Getenv("HOME"), ".cursor", "hooks.json")
+}
+
+func ClaudeSettingsPath() string {
+	return filepath.Join(os.Getenv("HOME"), ".claude", "settings.json")
+}
+
+func MergeCursorHooks(path string, force bool) error {
+	doc := map[string]any{"version": 1, "hooks": map[string]any{}}
+	if data, err := os.ReadFile(path); err == nil {
+		_ = json.Unmarshal(data, &doc)
+	}
+	hooks, _ := doc["hooks"].(map[string]any)
+	if hooks == nil {
+		hooks = map[string]any{}
+		doc["hooks"] = hooks
+	}
+	addHook(hooks, "stop", cursorHookCmd, force)
+	cfg, _ := config.LoadDefault()
+	if cfg.Events.Tool {
+		addHook(hooks, "afterShellExecution", cursorToolCmd, force)
+	}
+	return writeJSON(path, doc)
+}
+
+func addHook(hooks map[string]any, name, command string, force bool) {
+	if existing, ok := hooks[name]; ok && !force {
+		_ = existing
+		return
+	}
+	hooks[name] = []any{map[string]string{"command": command}}
+}
+
+func MergeClaudeSettings(path string, force bool) error {
+	doc := map[string]any{}
+	if data, err := os.ReadFile(path); err == nil {
+		_ = json.Unmarshal(data, &doc)
+	}
+	hooks, _ := doc["hooks"].(map[string]any)
+	if hooks == nil {
+		hooks = map[string]any{}
+		doc["hooks"] = hooks
+	}
+	setClaudeHook(hooks, "Stop", claudeStopCmd, force)
+	cfg, _ := config.LoadDefault()
+	if cfg.Events.Idle {
+		setClaudeHook(hooks, "Notification", claudeIdleCmd, force)
+	}
+	return writeJSON(path, doc)
+}
+
+func setClaudeHook(hooks map[string]any, event, command string, force bool) {
+	if _, ok := hooks[event]; ok && !force {
+		return
+	}
+	hooks[event] = []any{
+		map[string]any{
+			"hooks": []any{
+				map[string]string{
+					"type":    "command",
+					"command": command,
+				},
+			},
+		},
+	}
+}
+
+func writeJSON(path string, doc any) error {
+	if err := os.MkdirAll(filepath.Dir(path), 0755); err != nil {
+		return err
+	}
+	data, err := json.MarshalIndent(doc, "", "  ")
+	if err != nil {
+		return err
+	}
+	data = append(data, '\n')
+	return os.WriteFile(path, data, 0644)
+}
+
+func InstallAll(force bool) error {
+	if err := config.Default().WriteDefault(config.DefaultPath()); err != nil {
+		return err
+	}
+	if err := MergeCursorHooks(CursorHooksPath(), force); err != nil {
+		return err
+	}
+	return MergeClaudeSettings(ClaudeSettingsPath(), force)
+}