Use ui_scale and dpi from preferences for font drawing.

On hi-dpi screens the fonts drawn in these addons is very small and they do not respect the ui scale preference either.

Change all addons except the following as I think they're more well maintained by others: archimesh, archipack, blenderkit. One last addon, space_view3d_stored_views, requires more work. Right now it is drawing text behind the overlays/shading popups; the maintainer of that addon should fix things all-up.