marcopan
f104c015a1
New evidence/formula_store.py: ConceptFormula (concept, columns, sql, status, sources) as a frontmatter-YAML + SQL-body unit, stored one-file-per-formula under <formulas>/<slug>-<n>.sql.md. save_formula is append-only (competing drafts and reviewed versions coexist); retrieve_formula(concept) returns all of them so the gate can surface candidates and let the reviewer choose. concept_formula_approved / concept_formula_rejected added to DecisionType (records the reviewer's choice; approved formulas travel with schema-linking). L1: test_formula (7 tests) -- retrieval by concept, save/reload roundtrip (SQL body preserved, frontmatter well-formed), multiple formulas per concept, empty on no-match / missing dir, decision-type existence, default draft status. Deferred: --kind formula on nsp search (needs search_cmd porting) wires retrieve_formula into the CLI; lands with the search command.