feat: harness VM stack (runner, measure-db, blackbox, Alloy, k6) and the 12 scenarios

Experiment design 5 and 7 for the harness VM (10.20.0.11): vm/harness/apply.sh pulls the secrets from Secret Manager,
compose runs runner:de076a7, measure-db, blackbox, Alloy (probe_success -> Mimir) and k6 under the campaign profile.
Scenario files C-K1..X-M2 are loaded by the runner. Harness ClusterRole gains replicasets get/list for rollout undo.

workloads/rbac/harness.yaml

@@ -17,6 +17,9 @@ rules:
   - apiGroups: ["apps"]
     resources: ["deployments", "deployments/scale"]
     verbs: ["get", "list", "watch", "patch"]
+  - apiGroups: ["apps"]
+    resources: ["replicasets"] # rollout undo reads the previous revision's pod template
+    verbs: ["get", "list"]
   - apiGroups: [""]
     resources: ["pods"]
     verbs: ["get", "list", "watch"]