初步实验使用KV数据库（pebble）存储缓存索引

internal/utils/kvstore/value_encoder.go

@@ -0,0 +1,23 @@
+// Copyright 2024 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
+
+package kvstore
+
+import "encoding/json"
+
+type ValueEncoder[T any] interface {
+	Encode(value T) ([]byte, error)
+	EncodeField(value T, fieldName string) ([]byte, error)
+	Decode(valueBytes []byte) (value T, err error)
+}
+
+type BaseObjectEncoder[T any] struct {
+}
+
+func (this *BaseObjectEncoder[T]) Encode(value T) ([]byte, error) {
+	return json.Marshal(value)
+}
+
+func (this *BaseObjectEncoder[T]) Decode(valueData []byte) (value T, err error) {
+	err = json.Unmarshal(valueData, &value)
+	return
+}