pytest: bring back direct imports of TempdirFactory, Testdir

The monkeypatch approach doesn't work for `import pytest;
pytest.TempdirFactory`.

Fix pytest-dev#9432.

src/_pytest/legacypath.py

@@ -245,9 +245,6 @@ def __str__(self) -> str:
         return str(self.tmpdir)
 
 
-pytest.Testdir = Testdir  # type: ignore[attr-defined]
-
-
 class LegacyTestdirPlugin:
     @staticmethod
     @pytest.fixture
@@ -284,9 +281,6 @@ def getbasetemp(self) -> LEGACY_PATH:
         return legacy_path(self._tmppath_factory.getbasetemp().resolve())
 
 
-pytest.TempdirFactory = TempdirFactory  # type: ignore[attr-defined]
-
-
 class LegacyTmpdirPlugin:
     @staticmethod
     @pytest.fixture(scope="session")

src/pytest/__init__.py

@@ -23,6 +23,8 @@
 from _pytest.fixtures import FixtureRequest
 from _pytest.fixtures import yield_fixture
 from _pytest.freeze_support import freeze_includes
+from _pytest.legacypath import TempdirFactory
+from _pytest.legacypath import Testdir
 from _pytest.logging import LogCaptureFixture
 from _pytest.main import Session
 from _pytest.mark import Mark
@@ -142,7 +144,9 @@
     "Stash",
     "StashKey",
     "version_tuple",
+    "TempdirFactory",
     "TempPathFactory",
+    "Testdir",
     "TestReport",
     "UsageError",
     "WarningsRecorder",