Add SAND-WP-0008: host telemetry and self-canary introspection

Workplan for default sand-boxer self-deploy, before/after host metrics,
stale sandbox inventory, and telemetry export for centralized analysis.

SCOPE.md

@@ -126,7 +126,8 @@ Additional boundaries:
 - **Registry:** scaffold present (`registry/indexes/capabilities.yaml` empty;
   `registry/capabilities/` placeholder); domain in index still `helix_forge`
   from scaffold — needs alignment to `infotech`
-- **Workplans:** `SAND-WP-0001` (State Hub bootstrap) in `ready`
+- **Workplans:** `SAND-WP-0001` finished; `SAND-WP-0002` active;
+  `SAND-WP-0008` proposed (host telemetry / self-canary)
 - **Lineage (external, not yet migrated):** `the-custodian/e2e-framework/`
   (CUST-WP-0028, completed) and `infra/build-machines/` (CUST-WP-0032)