[Core] Add integration test for full evaluation pipeline

[SaharPak]

Add an integration test that runs the full evaluate() function end-to-end.

In packages/core/src/__tests__/, create a test file that:

1. Loads a fixture CV from __fixtures__/
2. Optionally loads a fixture JD
3. Calls evaluate() with both
4. Asserts the result has all required fields (score, dimensions, issues, strengths, archetype)
5. Asserts the score is within a reasonable range
6. Asserts known issues are detected (e.g., a CV with 'passionate about AI' should flag it)
7. Asserts archetype detection works (a Python/ML heavy CV should detect as ai-engineer)

Use vitest. This is the foundation for the golden fixture test harness described in ARCHITECTURE.md.