raise error if the constraint is created on a field that doesn't exist

[xantrac]

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Leave anything that you believe does not apply unchecked.

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[zachdaniel]

Thanks for the PR! I think this behavior is valuable but would be better placed in a verifier on the data layer extension. This will give errors at compile time instead of when generating migrations. See this verifier for example: https://github.com/ash-project/ash_postgres/blob/main/lib/verifiers/validate_identity_index_names.ex

[xantrac]

Thanks for the PR! I think this behavior is valuable but would be better placed in a verifier on the data layer extension. This will give errors at compile time instead of when generating migrations. See this verifier for example: https://github.com/ash-project/ash_postgres/blob/main/lib/verifiers/validate_identity_index_names.ex

Sounds good!