Increase test coverage from 70% to 80%

[nathanvale]

Summary

After temporarily reducing coverage threshold from 80% to 70% to unblock main branch, we need to increase test coverage to reach the 80% target.

Current Status

• Coverage threshold: 70% (temporarily reduced)
• Current coverage: ~69-74%
• Target coverage: 80%

Tasks

• Analyze current coverage reports to identify uncovered code
• Add tests for uncovered functions and branches
• Focus on critical paths and edge cases
• Ensure new tests follow verbose testing guidelines
• Update coverage threshold back to 80% once target is reached

Acceptance Criteria

• Line coverage ≥ 80%
• Function coverage ≥ 80%
• Branch coverage ≥ 80%
• Statement coverage ≥ 80%
• All tests pass locally and in CI
• Coverage threshold restored to 80% in packages/testkit/src/config/vitest.base.ts

Related

• Fixes #[main branch coverage failure]
• Part of broader test quality improvement initiative