Fix ArgoCD ServerSideDiff permanent OutOfSync diffs

Add explicit CRD/API defaults to manifests that were causing ArgoCD's
SSA dry-run to produce results different from live state:

- HTTPRoutes: add group, kind, weight defaults to parentRefs/backendRefs
- Kyverno ClusterPolicies: add skipBackgroundRequests, allowExistingViolations
- Tetragon TracingPolicies: add return, maxData, resolve, returnCopy defaults
- Gateway certificateRefs: add group="" default
- Guacamole Gateway: add group="" to certificateRefs

Add ignoreDifferences for resources that legitimately differ:
- Cilium cert Secrets (auto-generated, data always differs)
- Istio ValidatingWebhookConfiguration failurePolicy (istiod mutates)
- Crowdsec LAPI Secrets (randomly generated)
- ServiceMonitor/PodMonitor relabeling action defaults
- StatefulSet volumeClaimTemplates apiVersion/kind defaults

Persist argocd-cm ignoreDifferences config in ArgoCD Helm values.

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

apps/guacamole/manifests/envoy-gateway.yaml

@@ -27,7 +27,8 @@ spec:
       tls:
         mode: Terminate
         certificateRefs:
-          - kind: Secret
+          - group: ""
+            kind: Secret
             name: guacamole-envoy-tls
 
 ---
@@ -38,7 +39,9 @@ metadata:
   namespace: guacamole
 spec:
   parentRefs:
-    - name: guacamole
+    - group: gateway.networking.k8s.io
+      kind: Gateway
+      name: guacamole
       sectionName: https
   hostnames:
     - guacamole.kube.huskypup.net
@@ -55,13 +58,19 @@ spec:
               type: ReplacePrefixMatch
               replacePrefixMatch: /
       backendRefs:
-        - name: guacamole
+        - group: ""
+          kind: Service
+          name: guacamole
           port: 8080
+          weight: 1
     # Standard root routing
     - matches:
         - path:
             type: PathPrefix
             value: /
       backendRefs:
-        - name: guacamole
+        - group: ""
+          kind: Service
+          name: guacamole
           port: 8080
+          weight: 1