Disallow initializing fields with themself

[dkorpel]

Trying to prevent a common user error: Super easy struct construction question that I'm embarrassed to ask.

This might need a deprecation, but let's try errors first to see how buildkite responds.

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Testing this PR locally

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[dkorpel]

Errors in buildkite projects:

https://github.com/sociomantic-tsunami/swarm/blob/5804f3ec3ec4f7b7d26637a766a1bdd3604e4047/src/swarm/neo/connection/ConnectionBase.d#L761C37-L761C45

https://github.com/CyberShadow/ae/blob/ee6918bcff0c3256b5e8c9f5dd2792d878448ea5/sys/file.d#L2651

https://github.com/gecko0307/dagon/blob/d953918b323781f0dc1a5a667fa45a1edd231831/src/dagon/graphics/shader.d#L223

[thewilsonator]

Errors in Phobos(!) dlang/phobos#10620

[Herringway]

gotta love seein' returns for a good diagnostic right away, eh?

[thewilsonator]

https://github.com/CyberShadow/ae/blob/ee6918bcff0c3256b5e8c9f5dd2792d878448ea5/sys/file.d#L2651

cc @CyberShadow

https://github.com/gecko0307/dagon/blob/d953918b323781f0dc1a5a667fa45a1edd231831/src/dagon/graphics/shader.d#L223

cc @gecko0307

[CyberShadow]

Fixed, thank you.

[thewilsonator]

dagon was fxed by gecko0307/dagon#96 do we need a new tag for build kite to pick it up or do we just need to rerun CI?