feat: LLM可自主操作提醒 — reminder_create/list/delete 工具

- 新增 GatewayClient HTTP 客户端，调用 Gateway /api/v1/reminders API
- 新增 3 个提醒工具：reminder_create / reminder_list / reminder_delete
- main.go 注册提醒工具，需 GATEWAY_URL + INTERNAL_SERVICE_TOKEN 环境变量
- AutonomousToolPolicy 白名单加入提醒工具，允许自主思考中创建提醒

Co-Authored-By: Claude <noreply@anthropic.com>

backend/ai-core/cmd/main.go

@@ -158,6 +158,12 @@ func main() {
 		log.Println("IoT 客户端未配置 (IOT_SERVICE_URL 和 IOT_DEBUG_SERVICE_URL 均为空)")
 	}
 
+	// 初始化 Gateway HTTP 客户端（提醒/日程等工具用）
+	gwBaseURL := getEnv("GATEWAY_URL", "http://localhost:8080")
+	gwToken := os.Getenv("INTERNAL_SERVICE_TOKEN")
+	gwClient := tools.NewGatewayClient(gwBaseURL, gwToken)
+	log.Printf("Gateway 客户端已就绪: %s", gwBaseURL)
+
 	// 初始化主机操控管理器 (沙箱执行 + 文件系统隔离)
 	hostSandbox := host.NewSandbox(host.DefaultSandboxConfig())
 	directBackend := host.NewDirectBackend(hostSandbox)
@@ -224,6 +230,14 @@ func main() {
 			toolRegistry.Register(wrapTool(tools.NewOSSystemTool(osManager), "os_system", "OS System Info", "system"))
 		}
 
+		// 提醒/日程工具（需要 Gateway 客户端）
+		if gwClient != nil && gwToken != "" {
+			toolRegistry.Register(wrapTool(tools.NewReminderCreateTool(gwClient, adminUserID), "reminder_create", "Create Reminder", "reminder"))
+			toolRegistry.Register(wrapTool(tools.NewReminderListTool(gwClient, adminUserID), "reminder_list", "List Reminders", "reminder"))
+			toolRegistry.Register(wrapTool(tools.NewReminderDeleteTool(gwClient, adminUserID), "reminder_delete", "Delete Reminder", "reminder"))
+			log.Println("[工具] 提醒工具已注册 (reminder_create, reminder_list, reminder_delete)")
+		}
+
 		visionProvider = nil
 		if configLoader != nil && configLoader.HasConfig() {
 			cfg := configLoader.GetConfig()