build code model via cmake-file-api

[christian-rauch]

"Extra Generators", such as CodeBlocks are deprecated since CMake 3.27 and will be removed in future.

Running catkin or colcon with CMake generator -G "CodeBlocks - Unix Makefiles" will show the error:

CMake Deprecation Warning:
  Support for "Extra Generators" like

    CodeBlocks

  is deprecated and will be removed from a future version of CMake.  IDEs may
  use the cmake-file-api(7) to view CMake-generated project build trees.

in the compile log.

The suggested way to build a model of the code is via the cmake-file-api. colcon-cmake already makes use of this to get the targets in the workspace. We can reuse the query by parsing the reply.

I tried to reuse the "FileApi" classes (FileApiParser, FileApiReader, FileApiQtcData) from the CMakeProjectManager inside the CMakeProjectManager::Internal namespace, but couldn't link them. I guess this is somewhat intended with the internal implementation.

In the end, I parsed the json file for the reply manually. It seems to work with a small workspace, but I have the feeling it is a bit slower than the original CodeBlocks file parsing.

This will only be supported for colcon for now. At least on Ubuntu, the only version that still supports ROS 1 officially uses an older CMake version and should not see these warnings.

Fixes #520.

[christian-rauch]

@Levi-Armstrong Could you test this to see if it behaves as expected? You can use the build artifacts to install this on Qt Creator 16. The cmake-file-api parser takes precedence over the CodeBlocks parser now. So this should work as soon as you update the plugin. But you may run this anyway on a clean workspace without the build and install folder, or at least remove all the *.cbp files from the build folder, in order to remove all traces of CodeBlocks.