chore(release): integrate Brio database stack

[kaanyagci]

Purpose

Integrate the reviewed isolated Brio databases, credential reconciliation, runtime observer, and database control receipt as a clean signed release branch.

Reviewed source

This branch reproduces the final reviewed trees from #9 through #12. It explicitly excludes #13 and all shared-lease work.

Validation

• Final tree exactly matches the reviewed feat(security): attest live Brio database controls #12 head.
• Every commit has a valid GPG signature.
• The complete local PostgreSQL CI suite passes, including failure injection, rollback, encrypted backup and restore, role isolation, and control receipts.
• CI uses the existing Makepad self-hosted Linux runner.
• Deployment remains blocked until required review and CI pass.

Review is requested from @idilsaglam.