Low Test Coverage: utils/transform.ts

[gitauto-ai]

Resolves #602

Summary

Add comprehensive unit tests for utils/transform.ts to reach 100% line, branch, and function coverage with minimal code changes.

Test Patterns

• Happy paths for all exported functions: correct transformation of valid inputs
• Edge cases: empty input, null/undefined, empty arrays/objects, boundary values
• Error handling: invalid types, malformed payloads, unsupported options; asserts precise error behavior
• Branch coverage: option flags, default/fallback paths, early returns, no-op scenarios
• Input integrity: verifies inputs are not mutated
• Idempotence where applicable: repeated transforms yield consistent results
• Large input sanity: handles sizable collections without errors or timeouts

git fetch origin
git checkout gitauto/issue-602-20260116-131446-udfa
git pull origin gitauto/issue-602-20260116-131446-udfa