[clang-tools-extra] [clangd] Add 'apply all clangd fixes' and 'apply all '_' fixes' QuickFixes (PR #79867)

[Tor Shepherd via cfe-commits]

torshepherd wrote:

Hmm I noticed another mini-issue. Ideally we shouldn't have a 'fix all clangd' quick fix if all of the issues come from the same source, only the 'fix all _' option

https://github.com/llvm/llvm-project/pull/79867