🧪 Replace distlib type ignores with stubs

The stubs are taken from the unmerged PR [[1]] upstream. MyPy is set
up to rely on them instead of the missing package type annotations.

[1]: https://github.com/pypa/distlib/pull/195

MANIFEST.in

@@ -5,6 +5,6 @@ include licenses/*.txt
 include requirements.txt
 recursive-include packaging *.py *.j2
 recursive-include test/integration *
-recursive-include test/sanity *.in *.json *.py *.txt *.ini
+recursive-include test/sanity *.in *.json *.py *.pyi *.txt *.ini
 recursive-include test/support *.py *.ps1 *.psm1 *.cs *.md
 recursive-include test/units *

lib/ansible/galaxy/collection/__init__.py

@@ -41,8 +41,8 @@ else:
     HAS_PACKAGING = True
 
 try:
-    from distlib.manifest import Manifest  # type: ignore[import]
+    from distlib.manifest import Manifest
-    from distlib import DistlibException  # type: ignore[import]
+    from distlib import DistlibException
 except ImportError:
     HAS_DISTLIB = False
 else:

test/sanity/code-smell/mypy/_type_stubs/distlib/__init__.pyi

@@ -0,0 +1,5 @@
+# NOTE: `distlib` is untyped as of 10 Oct 2025.
+# NOTE: This should be removed once types are upstream.
+# Ref: https://github.com/pypa/distlib/pull/195
+
+class DistlibException(Exception): ...

test/sanity/code-smell/mypy/_type_stubs/distlib/manifest.pyi

@@ -0,0 +1,8 @@
+# NOTE: `distlib` is untyped as of 10 Oct 2025.
+# NOTE: This should be removed once types are upstream.
+# Ref: https://github.com/pypa/distlib/pull/195
+
+class Manifest:
+    def __init__(self, base: str | None = ...) -> None: ...
+    def process_directive(self, directive: str) -> None: ...
+    def sorted(self, wantdirs: bool = ...) -> list[str]: ...

test/sanity/code-smell/mypy/ansible-core.ini

@@ -13,6 +13,8 @@ strict_optional = False
 # See: https://github.com/python/mypy/issues/4717
 disable_error_code = attr-defined,safe-super,type-abstract
 
+mypy_path = ${MYPY_CONFIG_FILE_DIR}/_type_stubs
+
 # Some controller unit tests use ansible_collections imports, both real and test-specific.
 # The real imports are not currently visible to mypy.
 # There's little point in exposing the test-specific imports.