[clang] [libclang/python] Add strict typing to clang Python bindings (#76664) (PR #78114)

[Jannick Kremer via cfe-commits]

DeinAlptraum wrote:

I'm planning to do one last split that contains all "logic" changes, after which this PR should contain only actual typing annotations and nothing else. Will open a PR for that other change one of these days

https://github.com/llvm/llvm-project/pull/78114