Create new NonSendMarker

[joshua-holmes]

Objective

Create new NonSendMarker that does not depend on NonSend.

Required, in order to accomplish #17682. In that issue, we are trying to replace !Send resources with thread_local! in order to unblock the resources-as-components effort. However, when we remove all the !Send resources from a system, that allows the system to run on a thread other than the main thread, which is against the design of the system. So this marker gives us the control to require a system to run on the main thread without depending on !Send resources.

Solution

Create a new NonSendMarker to replace the existing one that does not depend on NonSend.

Testing

Other than running tests, I ran a few examples:

• window_resizing
• wireframe
• volumetric_fog (looks so cool)
• rotation
• button

There is a Mac/iOS-specific change and I do not have a Mac or iOS device to test it. I am doubtful that it would cause any problems for 2 reasons:

1. The change is the same as the non-wasm change which I did test
2. The Pixel Eagle tests run Mac tests

But it wouldn't hurt if someone wanted to spin up an example that utilizes the bevy_render crate, which is where the Mac/iSO change was.

Migration Guide

If NonSendMarker is being used from bevy_app::prelude::*, replace it with bevy_ecs::system::NonSendMarker or use it from bevy_ecs::prelude::*. In addition to that, NonSendMarker does not need to be wrapped like so:

fn my_system(_non_send_marker: Option<NonSend<NonSendMarker>>) {
    ...
}

Instead, it can be used without any wrappers:

fn my_system(_non_send_marker: NonSendMarker) {
    ...
}

[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-18301

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.

[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-18301

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.

[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-18301

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.

[chescock]

Looks good!