utils: clean up test-to-requirement traceability

Apply the test-to-requirement traceability clean-up described in #522 to the Utils component (`score/utils/`).

Replace legacy raw-symbol `Verifies` links and unsupported metadata with mandated `FullyVerifies` or `PartiallyVerifies` links to the current `comp_req__utils__...` needs, together with `TestType`, `DerivationTechnique`, and self-contained `Description` metadata.

Review every C++ gtest under `score/utils/` against the current Utils requirements. Ensure each linked test genuinely exercises its assigned requirement, requirements accurately describe the implemented behavior, and non-functional requirements that are only verifiable by inspection are not given artificial test coverage.

Start with the traceability clean-up described in #522 and inspect the C++ gtests under score/utils/ against the current Utils requirements. Review each requirement link and its TestType, DerivationTechnique, and Description metadata. Done means links use the mandated verification forms, metadata is self-contained, tests match their requirements, and inspection-only requirements have no artificial coverage.

Written by the indexing model from the issue text.