improvement: validate cross-field dependencies in graphql DSL options at compile time

[nallwhy]

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• Bug fixes include regression tests
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• Features include unit/acceptance tests
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• Update dependencies

Summary

• Add compile-time validation for cross-field dependencies between graphql DSL options
• Error when show_fields and hide_fields overlap (contradiction)
• Warn when options like sortable_fields, filterable_fields, nullable_fields, field_names, relationships, paginate_relationship_with, attribute_input_types reference fields that are not visible (hidden or not in show_fields)
• Warn when paginate_relationship_with, filterable_fields, field_names, nullable_fields reference relationships excluded from the relationships option

[Copilot]

Pull request overview

This PR adds a new Spark DSL verifier to validate cross-field dependencies among graphql DSL options for AshGraphql resources, raising on contradictions and emitting compile-time warnings for configurations that would have no runtime effect.

Changes:

• Introduces AshGraphql.Resource.Verifiers.VerifyFieldDependencies to detect show_fields/hide_fields contradictions and warn on references to non-visible or excluded relationship fields.
• Registers the new verifier in the AshGraphql resource extension verifier pipeline.
• Adds a comprehensive ExUnit test suite covering contradiction errors and the expected warning scenarios.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
lib/resource/verifiers/verify_field_dependencies.ex	New verifier implementing compile-time cross-option dependency checks (errors + warnings).
lib/resource/resource.ex	Registers the new verifier in the extension’s @verifiers list.
test/verify_field_dependencies_test.exs	Adds unit tests validating contradictions and warning behavior across supported options.

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[zachdaniel]

🚀 Thank you for your contribution! 🚀