ENH: Add typehints to python wheel packages

See https://peps.python.org/pep-0561/#stub-only-packages
Packaging typehints with package so use "itk", if making separate typehint
package use "itk-stubs"
set(ITK_STUB_BASENAME "itk")

The typehint files provide improved IDE introspection
capabilities for ITK.

Wrapping/CMakeLists.txt

@@ -83,8 +83,12 @@ set(CXX_TEST_PATH ${EXECUTABLE_OUTPUT_PATH})
 # Additional files for installation
 ###############################################################################
 
+# See https://peps.python.org/pep-0561/#stub-only-packages
+# Packaging typehints with package so use "itk", if making separate typehint
+# package use "itk-stubs"
+set(ITK_STUB_BASENAME "itk")
 # ITK_STUB_DIR: all stub files are stored in this directory
-set(ITK_STUB_DIR "${ITK_DIR}/Wrapping/Generators/Python/itk-stubs" CACHE INTERNAL "where python interface files are stored.")
+set(ITK_STUB_DIR "${ITK_DIR}/Wrapping/Generators/Python/${ITK_STUB_BASENAME}" CACHE INTERNAL "where python interface files are stored.")
 file(MAKE_DIRECTORY ${ITK_STUB_DIR})
 
 # ITK_PKL_DIR: all temporary pickled object AST representations stored here

Wrapping/Generators/Python/CMakeLists.txt

@@ -181,7 +181,7 @@ if(NOT EXTERNAL_WRAP_ITK_PROJECT)
   WRAP_ITK_PYTHON_BINDINGS_INSTALL(/itk/support "ITKCommon" ${ITK_WRAP_PYTHON_FILES})
   WRAP_ITK_PYTHON_BINDINGS_INSTALL(/itk/Configuration "ITKCommon" "${ITK_CONFIGURATION_INIT_MODULE}")
   WRAP_ITK_PYTHON_BINDINGS_INSTALL(/itk "ITKCommon" ${ITK_INIT_MODULE})
-  install(DIRECTORY ${ITK_STUB_DIR}/ DESTINATION ${PY_SITE_PACKAGES_PATH}/itk-stubs)
+  install(DIRECTORY ${ITK_STUB_DIR}/ DESTINATION ${PY_SITE_PACKAGES_PATH}/${ITK_STUB_BASENAME})
 endif()