feat: Phase 1 FDA host-operator Role and railiance01 pilot (WP-0009 T02–T07)

Lock DEC-FDA-001 working defaults; add roles/host-operator package with
OS/security and load protocols; scaffold eng-coulomb-railiance01-ho-001
with bound agent, vault, ramp checklists, and Kai quote/ledger.

engagements/pilots/eng-coulomb-railiance01-ho-001/request.yaml

@@ -0,0 +1,33 @@
+apiVersion: kaizen.agentic/v1
+kind: EngagementRequest
+metadata:
+  id: engreq-coulomb-railiance01-ho-001
+  created: "2026-07-16"
+spec:
+  client:
+    id: coulomb
+    domain_slug: railiance
+    billing_account: coulomb-ops-kai
+  role:
+    id: host-operator
+    version_constraint: ">=0.1.0 <1.0.0"
+  targets:
+    - kind: host
+      id: railiance01
+      inventory_ref: railiance-hosts
+      notes: "k3s production; forgejo/apps workloads; coulomb ecosystem"
+  duty:
+    health_review: daily
+    os_security_pass: weekly
+    load_review: daily
+    timezone: Europe/Berlin
+  access:
+    requested_classes: [host_observe, privileged_ops]
+    cert_identity_hint: agt
+  knowledge:
+    vault_placement: pilot_in_supplier_repo
+    confidentiality: client_owned
+  commercial:
+    currency: kai
+    trial: true
+    quote_requested: true