[clang] [LifetimeSafety] Impove `[[clang::lifetimbound]]` violation diagnostics (PR #196824)

[Utkarsh Saxena via cfe-commits]

usx95 wrote:

I would prefer the PR to be split since these are largely unrelated changes (this verification and annotation location)

https://github.com/llvm/llvm-project/pull/196824