Integration test suite: Drug discovery domain

[CaliLuke]

Port/create a drug discovery domain integration test suite similar to Python's test_drug_discovery_queries.py.

Schema: compounds, targets, trials, interactions, diseases with relations (interacts-with, treats, tested-in).

Test coverage:

• Molecular relationship queries (compound → target interactions)
• Pathway traversals (compound → target → disease)
• Trial result aggregations (success rates, dosage stats)
• Multi-attribute filtering on compounds (molecular weight, solubility)
• Complex graph patterns (compounds sharing targets)

File: gotype/integ_drug_test.go
Build tag: //go:build cgo && typedb && integration