fix(db): preserve binary array values through backups

Read bytea arrays as PostgreSQL text before driver parsing so null elements, dimensions, and bounds survive JavaScript restores. Gate binary SQL in the default suite and verify both real engines and automatic fallback. Stream qualification archive hashes and share the dedicated database URL guard.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

.github/workflows/backup-checkpoint-qualification.yml

@@ -4,6 +4,7 @@ on:
     paths:
       - 'packages/db/**'
       - 'server/src/services/*backup*'
+      - 'server/src/lib/dedicated-test-database-url.ts'
       - 'server/src/__tests__/*backup*'
       - 'server/src/__tests__/fixtures/database-backup-worker.ts'
       - 'server/src/index.ts'