feat: 引入 Logger 接口抽象，支持自定义日志实现

- 新增 Logger 接口定义，支持 zap/slog 等自定义实现
- 新增 CloserLogger 接口用于支持关闭操作
- Engine 新增 SetLogger/GetLogger 方法使用接口
- 新增 compat.go 兼容层，保留 reco 兼容方法
- 新增 slog 适配器示例
- 删除 zap 示例
- Context.GetLogger() 返回接口类型

logger.go

@@ -0,0 +1,23 @@
+// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+// Copyright 2024 WJQSERVER. All rights reserved.
+// All rights reserved by WJQSERVER, related rights can be exercised by the infinite-iroha organization.
+package touka
+
+// Logger 是日志接口，支持多种日志库实现（reco、zap、logrus 等）
+// 用户可以通过实现此接口来替换默认的日志实现
+type Logger interface {
+	Debugf(format string, args ...any)
+	Infof(format string, args ...any)
+	Warnf(format string, args ...any)
+	Errorf(format string, args ...any)
+	Fatalf(format string, args ...any)
+	Panicf(format string, args ...any)
+}
+
+// CloserLogger 可选扩展接口，支持关闭操作
+// 如果 Logger 实现了此接口，Engine 在关闭时会调用 Close()
+type CloserLogger interface {
+	Logger
+	Close() error
+}