Module pipeline 

Main classification pipeline.

Runs classification in priority order:

1. User-provided CAS → HS mappings (confidence = 1.0)
2. Embedded static rule table (CAS + shape + purity)
3. SMILES-based rule engine (v0.3)
4. LLM fallback via [LlmClassifier] trait hook (v0.4, llm feature)

Structs

HsPipeline

Main HS code classification pipeline.

PipelineConfig

Configuration for the classification pipeline.