[Bugfix] Backport request id validation to v0

[joerunde]

This PR:

• Backports the request id uniqueness validation from the v1 engine to the v0 engine. This prevents the engine from hanging on requests with duplicate request ids and failing to shutdown without kill -9
• Changes the KeyError to a ValueError for one of the two places where the request id validation is done in the v1 engine. This causes requests with duplicate IDs to result in a 400 instead of a 500 error

FIX #10583

[github-actions]

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[DarkLight1337]

Thanks for fixing!