Server-side apply for the argocd Application

Argo CD v3's own CRDs (applications, applicationsets, appprojects) embed
large schemas that exceed the 256KiB last-applied-configuration annotation
a client-side apply writes — the same reason cert-manager and
external-secrets already use this. Without it the upgrade sync fails on
the CRDs rather than on anything in the release.

ServerSideDiff comes with it for the same reason as the other three, and
becomes belt-and-braces once the upgraded Argo CD's schema matches the
cluster.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LEsTefWWifp4ikvhHF5s6N

values/incubator-infra-gke-toolshed-prd-usc1-values.yaml

@@ -34,6 +34,16 @@ appSpec:
     namespace: argocd
     chartDir: argo-cd
     valuesDir: argocd-admin-prd
+    # Argo CD v3's own CRDs (applications, applicationsets, appprojects)
+    # embed large schemas, past the 256KiB last-applied-configuration limit
+    # a client-side apply writes — the same reason cert-manager and
+    # external-secrets use this.
+    serverSideApply: true
+    # And therefore the same stale-schema diff problem: see the contour
+    # entry. Once the upgrade lands, Argo CD's schema matches this cluster
+    # and this becomes belt-and-braces rather than load-bearing.
+    compareOptions:
+      - ServerSideDiff=true
   - name: gitea
     nameOverride: gitea
     namespace: gitea