rename completed tasks, hook to claude memory changs

.scratch/alpha-hardening/issues/20-validator-service-token_completed.md

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+Status: done
+
+# 20 — Validator service token for `/v1/billing/forfeit`
+
+## What to build
+
+Define and implement a **validator service token** distinct from client API keys and admin sessions. The validator process must authenticate when calling `POST /v1/billing/forfeit`; arbitrary Bearer strings and client API keys must be rejected. This is a checklist subtask for issue 02 and should normally land in the same PR as the unified auth middleware.
+
+Per [ADR-0017 §4](../../docs/adr/0017-tracker-authentication-and-authorization.md): forfeit accepts **validator service identity or admin session** only.
+
+## Configuration
+
+| Item | Alpha default |
+|---|---|
+| Env var | `MESHNET_VALIDATOR_SERVICE_TOKEN` (tracker + validator) |
+| Config flag | `--validator-service-token` / tracker config file equivalent |
+| Header format | `Authorization: Bearer <service-token>` with a dedicated prefix or separate header scheme documented in runbooks (e.g. `Authorization: Service <token>` — pick one and test consistently) |
+| Rotation | Manual: set new token on tracker + validator, restart both; document zero-downtime rotation as post-alpha |
+
+## Rejection rules
+
+- Client API keys (`sk-mesh-…`) → **403** on forfeit (even if valid for inference)
+- Non-empty garbage Bearer → **401/403**
+- Missing auth → **401**
+- Valid validator service token → **200** (existing forfeit semantics)
+- Admin session → **200** (operator override)
+
+## Test-first
+
+1. Red: validator (or test client) posts forfeit with a valid API key — must fail after fix.
+2. Red: `Authorization: Bearer garbage` — must fail (covered by issue 02; this issue defines the accepted token).
+3. Green: configured service token succeeds; wrong token fails.
+
+## Acceptance criteria
+
+- [ ] Service token configurable via env/flag on tracker and validator
+- [ ] Unified auth middleware resolves service token → `validator` role (issue 02)
+- [ ] API keys explicitly rejected on forfeit path
+- [ ] Integration test: validator client with service token forfeit succeeds; API key forfeit fails
+- [ ] Runbook stub: rotation procedure (manual alpha)
+
+## ADR links
+
+- [ADR-0017](../../docs/adr/0017-tracker-authentication-and-authorization.md) §4
+
+## Related
+
+- `02-a2-unified-auth-boundary_completed.md` — middleware + role checks
+
+## Blocked by
+
+- `02-a2-unified-auth-boundary_completed.md`