Add tests for StatusCode variant creation from uint

[Copilot]

Proposed changes

Added comprehensive test coverage for the existing feature that allows creating Variant objects from uint and uint[] with StatusCode TypeInfo. Tests verify that the Variant value can be properly cast to StatusCode or StatusCode[].

Test Coverage:

• Scalar: new Variant(uint, TypeInfo.Scalars.StatusCode) → cast to StatusCode
• Array: new Variant(uint[], TypeInfo.Arrays.StatusCode) → cast to StatusCode[]
• Edge cases: empty arrays, single elements, various status code values (Good, BadNodeIdInvalid, custom codes)

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• Enhancement (non-breaking change which adds functionality)
• Test enhancement (non-breaking change to increase test coverage)
• Breaking change (fix or feature that would cause existing functionality to not work as expected, requires version increase of Nuget packages)
• Documentation Update (if none of the other choices apply)

Checklist

• I have read the CONTRIBUTING doc.
• I have signed the CLA.
• I ran tests locally with my changes, all passed.
• I fixed all failing tests in the CI pipelines.
• I fixed all introduced issues with CodeQL and LGTM.
• I have added tests that prove my fix is effective or that my feature works and increased code coverage.
• I have added necessary documentation (if appropriate).
• Any dependent changes have been merged and published in downstream modules.

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