Use @boolean for true and false in highlights

[everdrone]

Release Notes:

• Fixed issue where true and false were highlighted as constants, ignoring the boolean highlight defined in themes.
  • This fix applies to: C, C++, Go, JSON, JSONC, Python, and Rust.

[maxdeviant]

@everdrone I pulled the addition of the raw keyword out into #25342, since it was unrelated to the other changes.

[maxdeviant]

Thank you!

[everdrone]

@maxdeviant I have noticed this PR might be conflicting with the other pull requests by @chbk, like #25333
What should we do? I noticed in his PRs for other languages like JSON, true and false will be treated as @constant.builtin.

If you point me in one direction I can repropose another PR with the addition of the raw keyword too

[maxdeviant]

@maxdeviant I have noticed this PR might be conflicting with the other pull requests by @chbk, like #25333 What should we do? I noticed in his PRs for other languages like JSON, true and false will be treated as @constant.builtin.

If you point me in one direction I can repropose a PR with the addition of the raw keyword too

I'm still in the process of reviewing the changes in those PRs.

Your PR here seems like a small, additive change that brings the boolean highlights in line with the way we highlight booleans in our other languages, so I'd like to proceed with it.