[FIX]: make entity linking deterministic across runs

[oussamahansal]

Description

Entity linking is nondeterministic. The same query on the same graph with the same topk returns different seed sets between runs — and sometimes a different number of seeds. On the demo KG, 5 identical runs produced 5 distinct seed sets.

Changes

• fuzzy_string.py — sorted(set(...)) for a hash-independent vocab order
• byokg_query_engine.py — list(dict.fromkeys(...)) for the seed union (order-preserving dedup) and sorted(explored_entities) for the path retriever input.

Problem

Related issue (if any): #

Testing

• Unit tests added/updated
• Integration tests added (as appropriate)
• Existing tests pass (pytest)
• Tested manually (describe below)

Checklist

• Code follows existing style and conventions
• License headers present on new files
• Documentation updated (if applicable)
• No breaking changes (or clearly documented)

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[github-actions]

BYOKG-RAG Coverage Report: The coverage is at unknown% (target: unknown%). Download the HTML report here.

[github-actions]

BYOKG-RAG Coverage Report: The coverage is at 95.0% (target: 80%). Download the HTML report here.

[noel-improv]

Nice on this, just one non-blocker

[github-actions]

BYOKG-RAG Coverage Report: The coverage is at 95.0% (target: 80%). Download the HTML report here.