test(benchmark): expand biological benchmark suite to 100 validated cases

[engkinandatama]

Description

This PR expands the biological benchmark test suite in tests/test_benchmark.py to 100 curated test cases, completing the Phase 1 milestone.

Benchmark Coverage (100 Cases)

• 1–15 & 51–65: Well-known human cancer, metabolism, and signaling genes (approved symbols).
• 16–25 & 66–75: Clinical aliases, historical names, and surface markers (HER2, p53, MLL, OCT4, p27Kip1, Bcl-xL, PD-1, PD-L1, CTLA-4, TNF-alpha, CD20, etc.).
• 26–33 & 76–85: NCBI Entrez Gene ID queries across key oncogenes and tumor suppressors.
• 34–41 & 86–92: UniProtKB accession lookups.
• 42–50 & 93–100: Model organism (Mus musculus, taxon 10090) cross-species queries covering official symbols, Entrez Gene IDs, and MGI accession IDs.

Validation Results

• Benchmark Suite: 100 passed in 384.15s (100% accuracy, exceeding the target KPI of $\ge 95%$).
• Full Unit Test Suite: 30 passed, 5 skipped (due to external Ensembl rate-limits) in 52.68s.