fix(charts): emit leading document separators in monitoring partials

The routerlib service-monitor and rbac partials open their conditional
bodies without a leading '---'. Include sites chain partials on
adjacent lines and rely on each partial to separate itself, so with
router.monitoring.prometheus.enabled=true the rendered ServiceMonitor
continues the preceding EPP Service document, forming one YAML document
with duplicate root keys. Helm parses that document last-key-wins as a
ServiceMonitor and the Service drops out of the release inventory: an
upgrade that enables monitoring deletes the live Service, a fresh
install with monitoring enabled never creates it, and Helm reports no
error. Observed on GKE with Helm v4.2.0.

The rbac partial fails the same way when the service-monitor partial
renders empty (prometheus enabled with a provider other than
prometheusoperator): its ClusterRole fuses onto the Service.

Add a leading '---' inside each conditional, matching
_leader-election-rbac.yaml.

Signed-off-by: Luke Van Drie <lukevandrie@google.com>

Author: LukeAVanDrie

config/charts/routerlib/templates/_rbac.yaml

@@ -1,5 +1,6 @@
 {{- define "llm-d-router.rbac" -}}
 {{- if .Values.router.monitoring.prometheus.enabled }}
+---
 kind: ClusterRole
 apiVersion: rbac.authorization.k8s.io/v1
 metadata:

config/charts/routerlib/templates/_servicemonitor.yaml

@@ -1,6 +1,7 @@
 {{- define "llm-d-epp.service-monitor" -}}
 {{- $monitoringProviderName := include "llm-d-router.monitoring.provider.name" . | lower -}}
 {{- if and .Values.router.monitoring.prometheus.enabled (eq $monitoringProviderName "prometheusoperator") }}
+---
 apiVersion: monitoring.coreos.com/v1
 kind: ServiceMonitor
 metadata: