ci-data-v7 — parquet-canonical cutover

v7 (2026-07-20, parquet-canonical cutover): the reference DB is now a BUILD PRODUCT — parquet sources + schema.sql are canonical (ADR075/076 lineage; cutover plan 2026-07-19). Subset now DERIVED from the rebuilt product (sha256 f760bab5c63ce879decd72cfe3bf51c569a5a4ba2a4a57e0ccbb5d90f5e6fa42, sqlite 3.53.1, double-build byte-identical; qa:regression 6/6 pre- and post-flip). Adds full per-table parquet (80 files, full-coverage export incl. 14.7M-row fact_qcew_annual) + canonical schema.sql. ingest_checkpoint is out of the governed estate (pre-flip drive backup preserves it). TIGER tarball carried unchanged from v3 lineage. Register-mode CSV artifacts (R1 pair, ricci, county_cz) live in-repo under src/babylon/data/reference/ — not release assets.