XY-1119: [ELF AMK P5.5] Add recoverable authority-plane drills for journal, memory, knowledge, and traces

[yvette-carlisle]

Summary

• Add authority-plane recovery drill fixture evidence for source, journal, memory, knowledge, proposal, trace, and audit records.
• Add benchmark validation/reporting for backup/PITR restore, degraded read labels, RPO/RTO, record preservation, idempotent outbox replay, Qdrant rebuild completeness, migration repair, and dead-letter handling.
• Update benchmark spec, runbook, evidence index/log, and drift audit for the new recovery drill contract.

Validation

• cargo make fmt
• cargo make lint-fix
• cargo make checks: 370 passed, 92 skipped
• Independent Decodex review checkpoint: clean for HEAD eb37739

Notes

• Fixture evidence is local synthetic benchmark evidence only.
• No hosted HA, standby failover, multi-region SLA, private-corpus, or provider-backed claim is made.