[clang-tools-extra] [clang-doc]: Enable horizontal wrapping on longer function definitions (PR #181417)

[Samrudh Nelli via cfe-commits]

SamrudhNelli wrote:

> Further, I'm not sure I follow your reasoning in the description. please elaborate on what you were trying to do with `{{^End}}`. IF there is a real bug int he mustache implementation, then we should fix that in the mustache library, but right now it does pass all core Mustache spec conformance tests, so we'll need an example and to compare that against the formal spec to determine 1) the right test, and 2) the correct fix.

Current code in main : 
<img width="1470" height="228" alt="image" src="https://github.com/user-attachments/assets/31bfac4e-bd6c-4bde-b040-95000504b255" />
Correct fix:
<img width="1483" height="249" alt="image" src="https://github.com/user-attachments/assets/9776216b-14a7-4f5c-a66e-49a43dbf5007" />

I will include the fix in my commit. When `{{^End}}` encounters a `nil` value, it bubbles back and checks the parent key. 
If we set the `End` explicitly to be false, we can prevent the issue.



https://github.com/llvm/llvm-project/pull/181417