[clang] [clang] Enforce 1-based indexing for command line source locations (PR #139457)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman commented:

Thank you for the fix! The change should come with a release note in `clang/docs/ReleaseNotes.rst` so users know about the improvement.

Otherwise, I think this is going in a reasonable direction.

https://github.com/llvm/llvm-project/pull/139457