[clang-tools-extra] [clangd] Improve Markup Rendering (PR #140498)

[via cfe-commits]

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@@ -118,8 +138,8 @@ class Document {
   BulletList &addBulletList();
 
   /// Doesn't contain any trailing newlines.
-  /// We try to make the markdown human-readable, e.g. avoid extra escaping.
-  /// At least one client (coc.nvim) displays the markdown verbatim!
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tcottin wrote:

Ok, I would propose to introduce the `CommentFormat` option with the following behaviour:

- `Plaintext` (default): the old escaping behaviour and no doxygen command parsing. The only thing I would still change is the paragraph termination with 2 newlines instead of 1.
- `Markdown`: this disables the escaping as implemented with this patch, but still does not enable doxygen comment parsing.
- `Doxygen`: same as `Markdown` but also enables doxygen comment parsing.

Do you agree @emaxx-google?

https://github.com/llvm/llvm-project/pull/140498