Make DEV schema regeneration repeatable and reconcile baseline drift

Finding exposed by MOVILBA-360 explicit DEV regeneration on 2026-09-08: drizzle/schema.ts baseline carries hand-corrections for malformed observaciones default and bigint numeric max, and lags DEV rutap_expedientes, fabricantes/carrocerias indexes/checks, and the current-history view. A full regeneration reintroduces malformed output and bundles unrelated schema drift. The scoped generated declaration splice used for 360 was a one-off, not an approved normal regeneration workflow. Own investigation and a repeatable correction process; no implementation now per coder02 ruling. Keep separate from MOVILBA-386 branch-based PROD targeting hazard. Acceptance: repeatable DEV generation with valid output and accounted-for baseline drift, without manual splicing or unrelated changes.