fix(db): repair fresh migration chain

docs/architecture/technical-debt.md

@@ -1,6 +1,6 @@
 # Technical debt
 
-Last reconciled: 2026-07-31
+Last reconciled: 2026-08-15
 
 This ledger contains verified engineering debt only. Product ideas belong in the roadmaps and
 operator/external dependencies belong in `BLOCKERS.md`.
@@ -40,6 +40,7 @@ operator/external dependencies belong in `BLOCKERS.md`.
 
 | Priority | Debt | Current decision / trigger |
 |---|---|---|
+| P1 | EF migrations and startup reconciliation still share historical schema ownership. Blank SQLite EF migration, populated upgrade, and fresh/restarted MariaDB now pass, but the two mechanisms remain tightly coupled. | Keep the compatibility bootstraps and provider-specific ordering covered by `MigrationChainTests`. Consolidate ownership only through an expand/verify/contract migration after a production restore rehearsal; do not rewrite applied migration history. |
 | P1 | `JobApplication` still duplicates opportunity data now owned by `Job`. | Startup now backfills missing `Job` rows and both create paths dual-write. Keep compatibility reads until the production report and restore rehearsal pass; observe one release, then remove the legacy columns. |
 | P1 | Background workers assume one API instance. Restart recovery is durable, but there is no row lease for concurrent workers. | Add database leasing only before deploying more than one backend replica. |
 | P2 | Production log aggregation is still deployment-owned; Compose now bounds each container's local logs to 3 × 10 MB. | Add an OTLP/Seq sink only before multi-host operation or when incident-response needs exceed `docker logs`. |