Add novelty search niching mode

[nikivanstein]

Summary

• add a novelty-search niching mode with an archive and nearest-neighbour scoring
• integrate novelty scoring into initialization and selection flow
• extend niching tests to cover novelty scoring and selection behavior

Testing

• uv run pytest tests/

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https://chatgpt.com/codex/tasks/task_e_6901d2f3d11c8321b24f621a60a40600

[chatgpt-codex-connector]

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[codecov]

Codecov Report

❌ Patch coverage is 85.36585% with 6 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
llamea/llamea.py	85.36%	6 Missing ⚠️

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