Harden transformation run recovery

[TonisOrmisson]

Summary

• persist an exact profile-owned staging relation key before execution DDL
• quarantine cleanup failures as started runs and reconcile only uniquely owned recorded staging
• migrate legacy workflow catalogs without inventing ownership and preserve pre-existing final relations

Validation

• 136 non-service tests passed after merging current main
• 60 workflow tests passed against specification PR 2
• compileall and diff checks passed
• independent review found no actionable findings

Dependency

Specification PR OpenStatSpec/specification#2 must merge first; this PR will then pin its final main commit before merge.