9b1b4b9e32
This patch includes code from D9891 and D12754, so credit goes to Juanfran and Dalai.
I updated the patches to work with `master` and with the new overlay toggle.
The reason to include both changes as part of one patch is that the dimmed dashed lines work much better together with colored wires.
Theme setting for dash opacity:
{F11370574, size=full}
{F11286177, size=full, autoplay, loop}
{F11149912, size=full}
For adding the overlay I used `SpaceImageOverlay` as reference, although I'm not familiar with this code so there might be mistakes.
Reviewed By: #user_interface, HooglyBoogly
Differential Revision: https://developer.blender.org/D12886