Audit ligand normalization

Confirm that all of these map to the same driver entities:
o CBD, cannabidiol
o THC, Δ9-THC, delta-9-THC, D9THC
o Δ8-THC should belong to the THC driver family but remain distinct from Δ9-THC in the evidence table.

No specific files or tests are listed in the payload. Start by locating where driver-entity aliasing and normalization are defined (likely the ligand mapping or evidence table source) and inspect current entries for CBD/cannabidiol and THC variants. Validate via the existing query or output that CBD/cannabinoid and THC/D9 aliases resolve consistently to the same entity, while Δ8-THC remains separate from Δ9-THC in the evidence table. The issue is done when those mappings are confirmed and documented by the current data/output checks.

索引モデルが issue の本文から書いたものです。