{
  "bundle_id": "bundle:sha256:...",
  "start_id": "dr:sha256:abc123",
  "generated_at": "2025-08-11T...",
  "summary": "Short human-readable summary of provenance & decision state",
  "timeline": [ ... ],               // ordered list of ancestor DR summaries
  "constraints_summary": [...],
  "key_evidence_refs": [...],        // UCXL addresses
  "goal_alignment": { "score": 0.82, "reasons": [...] },
  "suggested_actions": [...],
  "escalation": { "required": false, "who": [] }, 
  "signatures": [...],               // leader + assembler sign
  "cache_hit": true|false
}