Lead Enrichment

Takes a minimal lead record ({ email, domain }) and returns a structured profile with role, seniority, company size, industry, and recent signals. Splits the output into confirmed (cited to a URL) and inferred (derived) fields so downstream skills can weight accordingly.

Key behaviors:

Never fabricates — returns null with a reason if a field cannot be confirmed.
Each confirmed field carries a source_url and retrieved_at timestamp.
inferred fields include a short rationale string.