feat: 任务完成时发送系统通知

- 新增 xcli_core/notification.py 跨平台通知模块
  - Windows: win10toast / PowerShell BurntToast / MessageBox
  - macOS: osascript display notification
  - Linux: notify-send / D-Bus
- process_conversation 结束后自动触发通知
- 新增 /notify 命令开关通知 (on/off)
- 通知在后台线程发送，不阻塞主流程
- 防重复通知冷却机制 (2秒)

xcli_core/notification.py

@@ -0,0 +1,214 @@
+"""
+跨平台系统通知模块
+当 AI 完成任务时，发送系统通知提醒用户
+支持 Windows / macOS / Linux
+"""
+import os
+import sys
+import subprocess
+import threading
+from typing import Optional
+
+
+class NotificationManager:
+    """跨平台系统通知管理器"""
+
+    def __init__(self):
+        self.enabled = True
+        self._platform = self._detect_platform()
+        self._last_title = ""
+        self._last_message = ""
+        self._cooldown_seconds = 2  # 防止重复通知的冷却时间
+        self._last_notify_time = 0
+
+    @staticmethod
+    def _detect_platform() -> str:
+        """检测当前平台"""
+        if os.name == 'nt':
+            return 'windows'
+        elif sys.platform == 'darwin':
+            return 'macos'
+        else:
+            return 'linux'
+
+    def set_enabled(self, enabled: bool):
+        """启用/禁用通知"""
+        self.enabled = enabled
+
+    def notify(self, title: str, message: str, force: bool = False):
+        """
+        发送系统通知
+
+        Args:
+            title: 通知标题
+            message: 通知内容
+            force: 是否忽略冷却时间强制发送
+        """
+        if not self.enabled:
+            return
+
+        # 防止重复通知
+        import time
+        now = time.time()
+        if (not force and
+            title == self._last_title and
+            message == self._last_message and
+            now - self._last_notify_time < self._cooldown_seconds):
+            return
+
+        self._last_title = title
+        self._last_message = message
+        self._last_notify_time = now
+
+        # 在后台线程发送，不阻塞主流程
+        thread = threading.Thread(
+            target=self._send_notification,
+            args=(title, message),
+            daemon=True
+        )
+        thread.start()
+
+    def notify_task_complete(self, task_summary: str = ""):
+        """通知任务完成的快捷方法"""
+        title = "小狸 Pro-CLI"
+        if task_summary:
+            # 截断过长的摘要
+            if len(task_summary) > 80:
+                task_summary = task_summary[:77] + "..."
+            message = f"任务已完成: {task_summary}"
+        else:
+            message = "任务已完成 ✓"
+
+        self.notify(title, message)
+
+    def notify_tool_complete(self, tool_name: str, result_summary: str = ""):
+        """通知工具执行完成"""
+        title = "小狸 Pro-CLI"
+        if result_summary:
+            if len(result_summary) > 60:
+                result_summary = result_summary[:57] + "..."
+            message = f"{tool_name}: {result_summary}"
+        else:
+            message = f"{tool_name} 执行完成 ✓"
+
+        self.notify(title, message)
+
+    # ── 平台实现 ──
+
+    def _send_notification(self, title: str, message: str):
+        """根据平台发送通知"""
+        try:
+            if self._platform == 'windows':
+                self._notify_windows(title, message)
+            elif self._platform == 'macos':
+                self._notify_macos(title, message)
+            else:
+                self._notify_linux(title, message)
+        except Exception:
+            # 通知失败不应影响正常流程
+            pass
+
+    def _notify_windows(self, title: str, message: str):
+        """Windows 通知 — 优先使用 win10toast，降级到 PowerShell"""
+        # 方法1: win10toast (pip install win10toast)
+        try:
+            from win10toast import ToastNotifier
+            toaster = ToastNotifier()
+            toaster.show_toast(title, message, duration=3, threaded=True)
+            return
+        except ImportError:
+            pass
+
+        # 方法2: PowerShell BurntToast 模块
+        try:
+            ps_script = f'''
+            [Windows.UI.Notifications.ToastNotificationManager, Windows.UI.Notifications, ContentType = WindowsRuntime] > $null
+            $template = [Windows.UI.Notifications.ToastNotificationManager]::GetTemplateContent([Windows.UI.Notifications.ToastTemplateType]::ToastText02)
+            $textNodes = $template.GetElementsByTagName("text")
+            $textNodes.Item(0).AppendChild($template.CreateTextNode("{title}")) > $null
+            $textNodes.Item(1).AppendChild($template.CreateTextNode("{message}")) > $null
+            $toast = [Windows.UI.Notifications.ToastNotification]::new($template)
+            [Windows.UI.Notifications.ToastNotificationManager]::CreateToastNotifier("{title}").Show($toast)
+            '''
+            subprocess.run(
+                ["powershell", "-ExecutionPolicy", "Bypass", "-Command", ps_script],
+                capture_output=True, timeout=5
+            )
+            return
+        except Exception:
+            pass
+
+        # 方法3: PowerShell 简单弹窗 (最后降级)
+        try:
+            escaped_msg = message.replace("'", "''")
+            escaped_title = title.replace("'", "''")
+            ps_cmd = (
+                f"Add-Type -AssemblyName System.Windows.Forms; "
+                f"[System.Windows.Forms.MessageBox]::Show('{escaped_msg}', '{escaped_title}')"
+            )
+            subprocess.run(
+                ["powershell", "-Command", ps_cmd],
+                capture_output=True, timeout=5
+            )
+        except Exception:
+            pass
+
+    def _notify_macos(self, title: str, message: str):
+        """macOS 通知 — 使用 osascript"""
+        escaped_title = title.replace('"', '\\"')
+        escaped_message = message.replace('"', '\\"')
+        script = f'display notification "{escaped_message}" with title "{escaped_title}"'
+        subprocess.run(
+            ["osascript", "-e", script],
+            capture_output=True, timeout=5
+        )
+
+    def _notify_linux(self, title: str, message: str):
+        """Linux 通知 — 优先 notify-send，降级到 D-Bus"""
+        # 方法1: notify-send (libnotify)
+        try:
+            subprocess.run(
+                ["notify-send", title, message, "-i", "dialog-information", "-t", "3000"],
+                capture_output=True, timeout=5
+            )
+            return
+        except FileNotFoundError:
+            pass
+
+        # 方法2: D-Bus 直接调用
+        try:
+            dbus_script = f'''
+import dbus
+bus = dbus.SessionBus()
+notify_obj = bus.get_object('org.freedesktop.Notifications', '/org/freedesktop/Notifications')
+notify_iface = dbus.Interface(notify_obj, 'org.freedesktop.Notifications')
+notify_iface.Notify('xiaoli-cli', 0, 'dialog-information', '{title}', '{message}', [], {{}}, 3000)
+'''
+            subprocess.run(
+                [sys.executable, "-c", dbus_script],
+                capture_output=True, timeout=5
+            )
+        except Exception:
+            pass
+
+
+# ── 全局单例 ──
+_notification_manager = None
+
+
+def get_notification_manager() -> NotificationManager:
+    """获取全局通知管理器单例"""
+    global _notification_manager
+    if _notification_manager is None:
+        _notification_manager = NotificationManager()
+    return _notification_manager
+
+
+def notify_task_complete(task_summary: str = ""):
+    """快捷函数：通知任务完成"""
+    get_notification_manager().notify_task_complete(task_summary)
+
+
+def notify_tool_complete(tool_name: str, result_summary: str = ""):
+    """快捷函数：通知工具执行完成"""
+    get_notification_manager().notify_tool_complete(tool_name, result_summary)