Add PEP 561 py.typed marker for type checker support

Author: mahyarmirrashed

MANIFEST.in

@@ -1 +1,2 @@
 include version.py
+include src/onepassword/py.typed

setup.py

@@ -71,9 +71,10 @@ def get_shared_library_data_to_include():
         "Programming Language :: Python :: 3.12",
         "Programming Language :: Python :: 3.13",
         "License :: OSI Approved :: MIT License",
+        "Typing :: Typed",
     ],
     cmdclass={"bdist_wheel": bdist_wheel},
-    package_data={"": get_shared_library_data_to_include()},
+    package_data={"": get_shared_library_data_to_include(), "onepassword": ["py.typed"]},
     install_requires=[
         "pydantic>=2.5",  # Minimum Pydantic version to run the Python SDK
     ],