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.

vm/harness/scenarios/C-G1.yaml

@@ -0,0 +1,32 @@
+# design 7 C-G1: grey zone, container. NetworkChaos delay api -> db-primary; pods stay Ready, p95 breaks. Correct answer: escalate.
+id: C-G1
+path: gray
+asset: container
+expected_layer: 2
+ground_truth_label: network_latency_api_to_db
+ground_truth_action: escalate
+description: NetworkChaos delay 300ms jitter 50ms, direction to, externalTargets 10.20.0.20, app=api
+notes:
+  open_item: "design 11.2: whether the delay applies through the flannel SNAT path is measured in the campaign"
+inject:
+  method: chaos
+  manifest: |
+    apiVersion: chaos-mesh.org/v1alpha1
+    kind: NetworkChaos
+    metadata:
+      namespace: chaos-mesh
+    spec:
+      action: delay
+      mode: all
+      direction: to
+      externalTargets: ["10.20.0.20"]
+      selector:
+        namespaces: [demo]
+        labelSelectors:
+          app: api
+      delay:
+        latency: "300ms"
+        jitter: "50ms"
+      duration: "20m"
+revert:
+  method: chaos_delete