Vscode-markdown: Add math support inside `\[ \]` and `\(\)` delimiters

[K-gihu]

It seems that this extension only support math code intellisense inside dollars sign. It will be lovely if \[\] and \(\) are also supported.

Screenshot

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TODOs

• [ ] Math rendering --- _upstream_
  https://github.com/waylonflinn/markdown-it-katex

• [ ] Intellisense (auto-completion) --- _help wanted_
  https://github.com/yzhang-gh/vscode-markdown/blob/850f2aaa30d50e7d3b6b42fc37c19f0d2ed254d5/src/completion.ts#L469-L481

• [ ] Toggle math environment --- _help wanted_
  https://github.com/yzhang-gh/vscode-markdown/blob/850f2aaa30d50e7d3b6b42fc37c19f0d2ed254d5/src/formatting.ts#L191-L199
  BTW, defining your own snippets is recommended as we need to add a new option to control the delimiter order if we choose to use the above command.

[yzhang-gh]

It can be done, although we haven't supported \(\) syntax yet

[Ruhrpottpatriot]

Another reason why especially \[...\] should be supported is because $$ is deprecated:
https://tex.stackexchange.com/questions/503/why-is-preferable-to

[yzhang-gh]

Another reason from #616 ($ used inside KaTeX mhchen extension).

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Upstream package https://github.com/waylonflinn/markdown-it-katex

[javioustlj]

When will have this new feature done?

[yzhang-gh]

(I've updated the issue description.)

[hhamud]

has this been fixed yet?