TextMate-compatible grammar for CG-3 (for Github syntax highlighting)

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It'd be nice to have syntax highlighting of CG-3 files in Github. They use linguist which reads TextMate-compatible syntax highlighting grammars:

• https://github.com/github/linguist/blob/master/CONTRIBUTING.md#adding-a-language
• https://github.com/github/linguist/blob/master/CONTRIBUTING.md#fixing-syntax-highlighting
• also docs: https://apeth.com/nonblog/stories/textmatebundle.html

so step 1 would be to get syntax highlighting of CG-3 files working in TextMate.

There's an interactive grammar tester at https://github-lightshow.herokuapp.com

https://github.com/Agrabski/antlr_to_sublime_convert seems like it can convert antlr's to textmate

[unhammer]

I think VSCode also uses TextMate, so that's another reason it'd be nice to have.

Can the tree-sitter grammar https://github.com/apertium/tree-sitter-apertium/tree/master/tree-sitter-cg be converted? (Preferably even as a build-step?)