add ament_cmake_python build type to ros2 pkg create

[darshmenon]

Closes #739

Adds ament_cmake_python as a valid --build-type option for ros2 pkg create, enabling users to scaffold a hybrid C++/Python package without having to manually write boilerplate.

What changes

verb/create.py

• Added ament_cmake_python to the --build-type choices
• Sets buildtool_depends to ['ament_cmake', 'ament_cmake_python']
• Reuses ament_cmake test dependencies (lint tooling)
• Exports build_type as ament_cmake in package.xml (correct — colcon treats it as a CMake package)
• Calls populate_ament_cmake_python and creates a scripts/ node when --node-name is given

api/create.py

• Added populate_ament_cmake_python — generates CMakeLists.txt and seeds the Python package directory with __init__.py and py.typed
• Extended create_package_environment to create the Python package source folder for ament_cmake_python

resource/ament_cmake_python/CMakeLists.txt.em

• New template: calls find_package(ament_cmake_python), ament_python_install_package(${PROJECT_NAME}), and optionally installs a node script

Usage

ros2 pkg create my_pkg --build-type ament_cmake_python --node-name my_node --dependencies rclpy

Generates a package with:

• CMakeLists.txt using ament_cmake_python
• my_pkg/__init__.py Python package
• scripts/my_node executable node
• Correct package.xml with both ament_cmake and ament_cmake_python buildtool deps

[fujitatomoya]

@darshmenon

can you use our PR template to fill in? did you use any AI tools like Claude/Copilot, that needs to be disclosed, it looks like pretty much AI generated report is pated in the PR header.

and DCO is missing.

btw this replaces #1080?

[christophebedard]

There's a PR for this already: #1080

[christophebedard]

There's a PR for this already: #1080

In this case, reviews of that PR are certainly welcome. Anyone can review a PR.