Architecture decision records

Create an ADR for a durable, hard-to-reverse choice that changes ownership, a public contract, dependency direction, storage or privacy boundaries, deployment topology, or the verification model. Use 0000-template.md, assign the next four-digit number, and link superseded ADRs in both directions.

ADRs record why a choice was made. Approved specifications describe intended behavior and the implementation reference describes current behavior. Update stale documents in the same change.