OpenGL migration + Qt6 compilation

Qt6 compilation depends on OpenGL migration so both changes are here.

In "normal" mode (OpenGL), it works fine.

In VBO mode, it is still not working, the ruler is displayed but neither states nor containers are displayed.

This is wayyyyyyyyyyy out of my knowledge but I'm still creating the MR to not lose the work.

Fixes: #23, #24 Closes: #23, #24

.gitlab/build.yml

@@ -18,7 +18,7 @@ build:
     - make install | tee -a ../vite-build-with-${NAME}
   parallel:
     matrix:
-      - NAME: [opengl, vbo, vulkan, plugins, parsers]
+      - NAME: [opengl, vbo, vulkan, plugins, parsers, qt6_vbo, qt6_vulkan]
   only:
     - merge_requests
     - master@solverstack/vite