[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:

I am not sure about the provided design.
I actually wanted to use the new config from the `markup::Document` class directly.
But the class is in the `clangdSupport` lib which does not have access to the config apparently.

Therefore I added a new `asEscapedMarkdown` function to the class.
This allows the users to determine what is needed based on the config and the client capabilities.

I fixed the missed formatting, but force pushed...
I think this canceled the approval of the CI again.

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