Implement local runtime persistence and policy gates

tests/fixtures/runtime-profile-plan-snapshot.json

@@ -0,0 +1,33 @@
+{
+  "data": {
+    "capabilities": [
+      "activation.plan",
+      "compaction.plan",
+      "policy.gate",
+      "profile.inspect",
+      "profile.plan",
+      "refresh.plan",
+      "retention.plan"
+    ],
+    "policy_gates": [
+      "label:project-local",
+      "durable_writes:review-gated",
+      "secrets:denied"
+    ],
+    "ready": true,
+    "required_adapters": [
+      "local-event-log",
+      "local-graph-store",
+      "markitect-context-package"
+    ]
+  },
+  "diagnostic_codes": [],
+  "operation": "profile.plan",
+  "operation_id": "op:0277ca92fd86",
+  "schema_version": "phase_memory.runtime.envelope.v1",
+  "subject": {
+    "id": "phase-memory-fixture-profile",
+    "kind": "memory_profile"
+  },
+  "valid": true
+}