Prepare fullscreen material bind groups in a prepare system

[IceSentry]

Objective

• FullscreenMaterial bind groups can be created ahead of time instead of creating them in the encoding system

Solution

• Create the bind groups in a prepare system

Testing

• I ran the example and it worked

[pcwalton]

Looks good as long as there's no problem with texture ID reuse.

[github-actions]

Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke!
You can review it at https://pixel-eagle.com/project/B04F67C0-C054-4A6F-92EC-F599FEC2FD1D?filter=PR-22886

If it's expected, please add the M-Deliberate-Rendering-Change label.

If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it.

[tychedelia]

This probably should be done in a generic place for any kind of post-processing system to use.

[IceSentry]

The issue is it also binds other things that are FullscreenMaterial specific so it's hard to generalize easily