docs: update docs about default thrift protocol from buffered to framed (#1422)

Author: Li2CO3

content/en/blog/releases/Kitex/release-v0_13_0.md

@@ -42,9 +42,17 @@ description: >
 
     User documentation: [StreamX Timeout Control](/docs/kitex/tutorials/basic-feature/streamx/streamx_timeout_control/)
 
-2. **Default Thrift transport protocol changed from Buffered to Framed** 
 
-    This change can leverage FastCodec for better performance.
+### **Special Change**
+
+1. **Default Thrift transport protocol changed from Buffered to Framed**
+
+   This change leverages FastCodec for higher codec performance. Since Kitex server supports protocol detection, this behavioral change is compatible. Framed protocol is generally supported by most thrift frameworks, and we assess the impact to be minimal. However, if the downstream does not support Framed protocol, please manually revert to the Buffered protocol as follows:
+
+```go
+cli := xxx.NewClient("service_name", client.WithTransportProtocol(transport.PurePayload))
+```
+
 
 ### **Others**
 1. **Code Product Simplification** 

content/en/docs/kitex/Tutorials/basic-feature/protocol/transport_protocol.md

@@ -34,11 +34,11 @@ If you want to use custom implementations for the message or transport protocol,
 
 #### Thrift
 
-1. Buffered: PurePayload (by default)
-2. configure Framed: prepend a 4-byte (int32) length before the Thrift pure payload
+1. Framed : prepend a 4-byte (int32) length before the Thrift pure payload. Kitex client uses Framed by default since v0.13.0, before v0.13.0, it used to be Buffered PurePayload.
+2. configure Buffered：add the below client option to set only send PurePayload
 
 ```go
-cli := xxx.NewClient("service_name", client.WithTransportProtocol(transport.Framed))
+cli := xxx.NewClient("service_name", client.WithTransportProtocol(transport.PurePayload))
 ```
 
 3. configure TTHeader: the protocol for Byted Mesh (Service Mesh 协议 )

content/zh/blog/releases/Kitex/release-v0_13_0.md

@@ -42,9 +42,15 @@ description: >
 
     详见 [StreamX 流超时控制](/zh/docs/kitex/tutorials/basic-feature/streamx/streamx_timeout_control/)。
 
-2. **Thrift 默认传输协议由 Buffered 改为 Framed**
+### **特殊变更**
 
-    这个变更可以利用 FastCodec 以获得更高的编解码性能。
+1. **Thrift 默认传输协议由 Buffered 改为 Framed**
+
+    这个变更可以利用 FastCodec 以获得更高的编解码性能。因为 Kitex 服务端支持协议探测，此行为变更是兼容的，通常支持 Apache Thrift 的框架都支持 Framed，我们评估影响不大，但如果你访问的下游不支持协议探测，或不支持 Framed，请手动参考下面的方式改回 Buffered 协议：
+
+```go
+cli := xxx.NewClient("service_name", client.WithTransportProtocol(transport.PurePayload))
+```
 
 ### **其他**
 1. 产物简化

content/zh/docs/kitex/Tutorials/basic-feature/protocol/transport_protocol.md

@@ -33,11 +33,11 @@ Kitex 目前支持两种传输协议：[TTHeader](/zh/docs/kitex/reference/trans
 
 #### Thrift
 
-1. 默认 Buffered：PurePayload
-2. 指定 Framed：PurePayload 前增加 4 个字节（int32）指定 Payload Size
+1. 默认 Framed 协议：在 PurePayload 前增加 4 个字节（int32）指定 Payload Size。Kitex 在 v0.13.0 及以后默认使用 Framed 协议，之前版本默认使用 Buffered PurePayload。
+2. 指定 Buffered：按下面的方式设置 option，手动设置为只发送 PurePayload
 
 ```go
-cli := xxx.NewClient("service_name", client.WithTransportProtocol(transport.Framed))
+cli := xxx.NewClient("service_name", client.WithTransportProtocol(transport.PurePayload))
 ```
 
 3. 指定 TTHeader：