chore(test): reuse EvaluationTracker to avoid multiple type-checks - #13652

Problem Resolved

No issue.

Summary of Changes

Follow-up to #13633

When doing nargo test --coverage we'd type-check every test because we couldn't reuse the cached context because it has an ever changing EvaluationTracker. However, we can remember what was the coverage before running the test (because comptime code can already increase coverage), then restore that before running each test. A Clone impl for EvaluationTracker was needed for this. Then we can remove the ContextState enum.

User Documentation

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PR Checklist

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.