gitops: upgrade Cilium to 1.19.1, add fujarna app, flux web UI, OIDC RBAC, and experiments

- Upgrade Cilium helm release from 1.18.5 to 1.19.1 with gatewayClass creation enabled
- Escalate gitea CI service account to cluster-admin, add OIDC cluster-admin binding
- Deploy fujarna app with full manifest set (deployment, service, PVC, httproutes, external secret)
- Add Flux web UI via flux-operator OCI repository and helm release
- Add experiments kustomization with test resources for gateway API and certificates

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

gitops/home-kubernetes/00-rbac/clusterrolebinding_oidc-admin.yaml

@@ -0,0 +1,15 @@
+apiVersion: rbac.authorization.k8s.io/v1
+kind: ClusterRoleBinding
+metadata:
+  name: oidc-cluster-admin
+roleRef:
+  apiGroup: rbac.authorization.k8s.io
+  kind: ClusterRole
+  name: cluster-admin
+subjects:
+- apiGroup: rbac.authorization.k8s.io
+  kind: User
+  name: https://idm.home.hrajfrisbee.cz/oauth2/openid/k8s#35842461-a1c4-4ad6-8b29-697c5ddbfe84
+- apiGroup: rbac.authorization.k8s.io
+  kind: User
+  name: novakj@idm.home.hrajfrisbee.cz