refactor(db): migrate CV extraction data

Move upload artifacts and extraction runs into an additive provider-aware migration. Preserve parsed results, indexes, and nullable artifact retention semantics.

docs/work-programmes/master-progress.md

@@ -48,6 +48,7 @@ Updated: 2026-08-30
 - Moved `GmailReviewDecisions` into a provider-aware migration, preserving existing SQLite decisions and closing the previously missing MariaDB table path.
 - Moved recovery codes, trusted devices, and revocable user sessions into one provider-aware authentication-support migration; populated legacy rows and indexes survive adoption, downgrade, and retry.
 - Moved Gmail, Microsoft Graph, and IMAP connection records into one provider-aware migration; encrypted credentials, sync state, uniqueness constraints, and historical repair paths are preserved.
+- Moved CV upload artifacts and extraction runs into a provider-aware migration; existing hashes, structured results, indexes, and nullable artifact retention semantics are preserved.
 
 ### In progress
 
@@ -78,7 +79,7 @@ Updated: 2026-08-30
 - Focused frontend: 2 suites, 6 tests passed.
 - Full frontend: 64 suites, 272 tests passed.
 - Next production build and TypeScript: passed.
-- Full backend: 726/726 tests passed after the email-provider JT-019 transfer.
+- Full backend: 727/727 tests passed after the CV extraction JT-019 transfer.
 - Portable Playwright launcher: resolved the user-local .NET 9 SDK; backend Release build passed with 0 warnings/errors.
 - Playwright: initial full run 9/10 exposed the intentional mobile Settings control change; updated focused rerun passed 1/1. A final complete browser rerun remains in the end-of-batch gate.
 - Focused backend match/intelligence verification: 34/34 passed.