add write back instructions

[gongrong1226]

When we use @binding.Args we can get the args of the enhanced method. Now with the array args, we can modify the input parameters of the target method. As demonstrated in BytekitDemo.java.

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[hengyunabc]

这个具体是什么场景下的需求？

[gongrong1226]

需要对任意方法入参进行修改时，比如servlet的流量截取。将入参servletRequest和servletResponse替换为自己的代理request和代理response，以获取request的inputStream中的请求内容和response的outputStream中的返回内容。
虽然使用instrument-api的方式能做到修改入参，但又不易对任意方法进行增强。