Should we align our `highlights.scm` with Zed better?

[DavisVaughan]

Full list of Zed highlight captures:
https://zed.dev/docs/extensions/languages#syntax-highlighting

Ours:
https://github.com/r-lib/tree-sitter-r/blob/main/queries/highlights.scm

For example, @conditional and @repeat don't exist on the Zed side.

We should probably restrict ourselves to those used in tree-sitter-python and tree-sitter-rust, they seem well aligned with Zed at first glance
https://github.com/tree-sitter/tree-sitter-rust/blob/master/queries/highlights.scm
https://github.com/tree-sitter/tree-sitter-python/blob/master/queries/highlights.scm

Possibly i pulled @conditional from the Scala one but no one else uses it so its probably wrong
https://github.com/tree-sitter/tree-sitter-scala/blob/d67fe3ba3879bd7ba74bd7f56c9a38fed241ba25/queries/highlights.scm#L196

GitHub documents what they want for tags.scm here, but nothing about highlights because I think that is provided by something else, but we'd want to be sure we are aligned with github highlights too if possible:
https://github.com/github/code-navigation?tab=readme-ov-file#tags-query

We also want to be mindful of what the neovim group uses

[aymennasri]

For zed-r, we had our way around these problems and had to capture the "key words" like for, while, repeat as @keyword, which made the highlighting easier but it would be more organized if we had the same highlight captures as Zed