Skip validation of null elements in array

[Phil-Ba]

Skips validation of null elements in arrays. There is no information at runtime if array elements are nullable, and validation will produce NPE in such cases

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Summary by cubic

Skip validation of null elements in arrays to prevent NPEs in generated okhttp-gson models when array items can be null at runtime.

• Bug Fixes
  • Array item validation now skips null and JsonNull entries before invoking item validators, preventing NPEs while preserving validation for non-null items.

^{Written for commit 2ab9c95. Summary will update on new commits.}