Architecture Decision Records (ADR) auto-generation and tracking

## Description

The manifesto positions ADRs, reference architectures, and security standards as the "governing ledger" in an agentic model. Git-ape currently generates architecture diagrams but does not produce or track Architecture Decision Records.

## Scope

1. **ADR generation** — After each deployment, auto-generate an ADR documenting: what was deployed, why (requirements), alternatives considered, trade-offs accepted (from WAF review), and the final architecture diagram.
2. **ADR directory** — `.azure/adrs/` with numbered ADR files following the standard format (Title, Status, Context, Decision, Consequences).
3. **ADR index** — Auto-maintained `INDEX.md` listing all ADRs with status.
4. **ADR references in deployments** — Each deployment's `metadata.json` links to its ADR.
5. **ADR evolution** — When a deployment is updated or destroyed, the ADR is amended with the change rationale.

## Acceptance Criteria

- [ ] Deployment pipeline generates an ADR after successful deployment.
- [ ] ADRs follow a consistent template (number, title, status, context, decision, consequences).
- [ ] ADR index is auto-maintained.
- [ ] Deployment metadata references the associated ADR.
- [ ] Updated deployments append to the existing ADR.