Use sip-build and python3_add_library for Qt5/Qt6

[sloretz]

I'm playing around with an alternative to #143.
Requires ros/rosdistro#50338

If I understand correctly, and I'm not sure that I do, python_qt_binding uses a Python script sip_configure.py to produce a Makefile that produces a cPython extension.

#143 uses sip-build, but sets it up to use pip install to generate the bindings. It ends up creating a separate function build_sip_6_binding to use this new approach with a configurable pyproject.toml.in template downstream in qt_gui_core.

This PR uses sip-build and the CMake function python3_add_library to build a cPython extension instead. This PR allows using sip-build on both Qt5 and Qt6 bindings, though right now I've only tested it with Qt5 on Noble. I'll need to update the Python code like @ahcorde has in #143 to import from PyQt6.

I used Gemini 3.1 Pro to help make this PR

[sloretz]

After looking into this a bit, this is too much to pursue right now. I'm going to close this for now. Nevermind, realized what I was doing wrong

[sloretz]

@ahcorde Willing to look at this PR? It replaces #143. The main feature is it builds the CPython extension using CMake instead of invoking pip.

[ahcorde]

Pulls: ros-visualization/rqt#339, ros-visualization/qt_gui_core#293, #157
Gist: https://gist.githubusercontent.com/ahcorde/729070b3a537f4c491871bd3250612a8/raw/1f70f4fdce2d0b6d5a67390b45cb7b5246863e0f/ros2.repos
BUILD args: --packages-above-and-dependencies rqt_gui_py rqt_py_common qt_dotgraph qt_gui qt_gui_cpp qt_gui_py_common python_qt_binding
TEST args: --packages-above rqt_gui_py rqt_py_common qt_dotgraph qt_gui qt_gui_cpp qt_gui_py_common python_qt_binding
ROS Distro: rolling
Job: ci_launcher
ci_launcher ran: https://ci.ros2.org/job/ci_launcher/18764

• Linux
• Linux-aarch64
• Linux-rhel
• Windows

[ahcorde]

• Linux
• Linux-aarch64
• Linux-rhel
• Windows

Related with ros2/ci#857 and ros2/ros2#1810