chore: initialize from backend template 0a6dd0e

docs/runbooks/template.md

@@ -0,0 +1,44 @@
+---
+title: Runbook — <TITLE>
+category: <CATEGORY>
+error_codes: [<ERROR_CODE_1>, <ERROR_CODE_2>]
+severity: <P1|P2|P3>
+owner: oncall
+last_updated: <YYYY-MM-DD>
+status: <stub|active>
+---
+
+# Runbook: <TITLE> (`runbook://<area>/<scenario>`)
+
+## Symptoms
+
+- What observable signals trigger this runbook?
+- Alert name, metric thresholds, log patterns
+
+## Diagnosis
+
+- Step-by-step diagnostic commands and queries
+- Log queries (Loki/CloudWatch)
+- Metric panels to check
+- Trace investigation approach
+
+## Action
+
+- Immediate mitigation steps
+- Configuration changes
+- Manual intervention procedures
+
+## Escalation
+
+- Conditions for severity upgrade (e.g., P2 → P1)
+- Who to page and when
+- Fallback procedures if on-call cannot resolve
+
+---
+
+> **Note**: This is the canonical runbook template.
+> Copy this file, rename it to match the `runbook://area/scenario` pattern (→ `area-scenario.md`),
+> fill in the frontmatter fields, replace section bodies with operational content,
+> then set `status: active`. `LEGACY_STUB_DEBT` in `RunbookCoverageContractTest` is temporary
+> containment for existing debt only; do not add a new stub there. Complete the runbook or adopt
+> the future owned, expiring debt ledger.