Disable camera_effects when debug draw is active

[ChristopheClaustre]

Devs for #49696

Bugsquad edit:

• Fixes Vulkan: "Display unshaded" option still shows camera effects such depth of field #49696

[Calinou]

Tested locally with Forward+ and Mobile (rebased on top of master 292e50e), it works as expected. Since this is done at a server level, this works both in the scenario where CameraEffects is set on the Environment resource and when it's set on the current Camera3D node.

Note that this also disables autoexposure while debug draw is active, but not the manual exposure multiplier. We could look into forcing this multiplier to be 1.0 when a debug draw mode is enabled. This already seems to be in place for the Overdraw debug mode, but not other debug draw modes.

[clayjohn]

Looks great to me. The comments are very helpful and I agree with your assessment

[clayjohn]

I've flagged this for merging in 4.3 despite it being an enhancement technically. But its a really safe change and only impacts debug drawing. I'm happy to be overruled if others disagree.

[ChristopheClaustre]

Last force-push was for rebasing on top of master and squashing commits for better integration.

[akien-mga]

Thanks!