Add comment injection

[thedadams]

The comment language extension handles highlighting comments like TODO: and FIXME(user):

[MrSubidubi]

Thanks again!

[juanmazake]

Thanks for the nice work guys! 👏
For some reason installing the extension doesn't bring the injections.scm file now, at least on my system. Would appreciate if you have any clue on this.

Some logs when installing:

Zed 0.217.3+stable.105.80433cb239e868271457ac376673a5f75bc4adb1

ERROR [language] missing required capture(s) in TOML indents TreeSitter query: indent
WARN  [language] unrecognized capture name 'comment' in TOML textobjects TreeSitter query

[thedadams]

They would need to release a new version of the extension with the changes.