FR: Add Codeblock Formatting

[BonjourL]

格式化代码块内的代码和格式化代码块外的代码

[pjkaufman]

I believe this is the English version of the request being made:

Code inside a formatted code block and code outside a formatted code block

@BonjourL , could you give a couple of examples and explain a little further on what you would like? I don't believe I understand what you are asking for.

Google translated to simplified Chinese: @BonjourL，你能举几个例子并进一步解释你想要什么吗？ 我不相信我明白你在问什么。

[BonjourL]

格式化代码块内的代码，比如有些java代码格式很乱，格式化后比较整齐

[peterkos]

Yes! this would be fantastic :pray:

Some ideas:

• Trim all trailing whitespace on focus leave of codeblock
• Ensure language is always specified
  • If lang is not set, option to always autoset a language

I'm not sure if we could integrate w/ a formatter (i.e., rustfmt), but that would be ultra cool.