dart: Add support for documentation comments (#19592)
Ömer Sinan Ağacan
and
Marshall Bowers
created
Closes #19590
Release Notes:
- N/A
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I'm unable to test this because rebuilding Zed with the changes does not
seem to use the changes. If maintainers could let me know how to test
these changes I'd like to verify that this really fixes #19590.
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Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>