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

[Tor Shepherd via cfe-commits]

torshepherd wrote:

Ah, awesome. In that case note that I'll make the option not show up when changes would have conflicting overlap ranges

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