[Bug]: packages are missing `py.typed` files

[DetachHead]

Bug Description

a py.typed file is required otherwise type checkers will treat the package as untyped. see https://typing.python.org/en/latest/spec/distributing.html#packaging-type-information

pyright for example complains on every import:

Steps to Reproduce

from microsoft_teams.cards import AdaptiveCard

Expected Behavior

no type error

Actual Behavior

pyright error:

Stub file not found for "microsoft_teams.cards" (reportMissingTypeStubs)

SDK Version

2.0.15

Python Version

3.14.6

Additional Context

No response

[russlan23]

I can take this as a focused packaging fix: add py.typed to each published microsoft_teams distribution, include it in the built wheels, and add a regression check that inspects the artifacts so the marker cannot be omitted again. I would keep runtime behavior unchanged. If this scope matches the Teams SDK team’s expectation, I can implement it.