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

[Jannick Kremer via cfe-commits]

DeinAlptraum wrote:

I rebased this on the other changes, so there's mostly relatively simple annotations left now. Still a few hundred of them though. @Endilll do you want me to split this further, or is this fine?

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