feat(fc-devicemgmt): add Kubernetes deployment manifests (#1)

Sprint 8 IMPL lane Cx-5: fc-devicemgmt K8s manifests (rebased onto main 2026-05-18; 13 files, +944).

Namespace + Web Deployment (replicas:2, MySQL backend) + Operator Deployment (replicas:1, KubeOps leader-elect) + Service + Certificate (step-ca-acme ClusterIssuer) + Traefik IngressRoute (devices.iamworkin.lan internal) + ServiceAccount + ClusterRole + ClusterRoleBinding + NetworkPolicy (CNI DNAT-aware backend ports) + OnePasswordItem (5-field consolidated) + ArgoCD Application bootstrap shape + lint coverage.

Follow-ups (not merge blockers):
- localhost/fc-devicemgmt-{web,operator}:v20260512-cx5 must be imported to all 3 RKE2 nodes; pods will ErrImageNeverPull until imported.
- 1Password vault item 'FlowerCore DeviceManagement Runtime' must be created with 5 fields before pods can start.
- DNS devices.iamworkin.lan -> 10.0.56.200 already present.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/fc-devicemgmt/certificate-web.yaml

@@ -0,0 +1,30 @@
+# Certificate for devices.iamworkin.lan.
+#
+# Preflight gate: FlowerCore.DNS / pfSense must contain an explicit A record:
+#   devices.iamworkin.lan -> 10.0.56.200
+# before this Certificate is synced. step-ca ACME cannot see the CoreDNS
+# wildcard, so missing pfSense DNS produces cert-manager HTTP-01 backoff
+# (feedback_pfsense_dns_required_for_acme).
+apiVersion: cert-manager.io/v1
+kind: Certificate
+metadata:
+  name: fc-devicemgmt-web-tls
+  namespace: fc-devicemgmt
+  labels:
+    app.kubernetes.io/name: fc-devicemgmt-web
+    app.kubernetes.io/component: web
+    app.kubernetes.io/part-of: flowercore
+    app.kubernetes.io/managed-by: argocd
+    flowercore.io/tenant-id: system
+    flowercore.io/created-by: bluejay-infra
+  annotations:
+    flowercore.io/dns-preflight: "devices.iamworkin.lan must resolve to 10.0.56.200 before ACME sync"
+spec:
+  secretName: fc-devicemgmt-web-tls
+  issuerRef:
+    name: step-ca-acme
+    kind: ClusterIssuer
+  dnsNames:
+    - devices.iamworkin.lan
+  duration: 720h
+  renewBefore: 240h