Add py.typed to mark library as typed

[atatarn]

Describe the bug

$ cat t.py

from pywa import WhatsApp

wa = WhatsApp(
    phone_id="...",
    token="...",
    waba_id="...",
)

$ mypy t.py
t.py:1: error: Skipping analyzing "pywa": module is installed, but missing library stubs or py.typed marker  [import-untyped]
t.py:1: note: See https://mypy.readthedocs.io/en/stable/running_mypy.html#missing-imports
Found 1 error in 1 file (checked 1 source file)

To Reproduce

No response

Expected behavior

Adding py.typed file to the package files will help mypy to analyze library types properly

pywa version

4.0.0

python version

3.12.3

os

No response

Additional context

No response

[yehuda-lev]

Hey, the library is completely type safe
But the library currently does not support mypy requirements, maybe later we will add support for it