Respect scope in required field validation for hidden/readonly fields

[profjellybean]

Ensure required field validation respects scope restrictions.

• Updated MetadataValidator to check current scope before enforcing required fields
• Skipped validation for fields marked hidden/readonly in the active scope
• Adjusted and added tests for scope-aware validation behavior
• Added test form definitions with scope declarations

References

Add references/links to any related issues or PRs. These may include:

• Fixes Required field validation ignores scope when fields are hidden/readonly #520

Description

Fix required field validation to respect scope restrictions. Validation now ignores required checks when the field is hidden or readonly in the current scope.

Instructions for Reviewers

This PR ensures metadata validation aligns with submission workflows by considering scope.

List of changes in this PR:

• Updated MetadataValidator to check scope before validating required fields
• Skipped validation for fields marked hidden/readonly in the active scope
• Adjusted existing tests to cover scope-aware validation
• Added new test form definitions with scope declarations

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