Remake vscode project configs generation

This is a new approach of generating vscode configs.

This is made to replicate the kde-builder environment as close as possible.

I have fully explored documentation on CMake Tools extension (how the environment variables are applied, and what is the general process).

I recreate environment for configure, build + install, and launch + debug.

This approach installs the target to the install_dir, and launches from there.

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Here is the docs toc, just to have it in hands when we will redo documentation in develop.kde.org