Enhance csi-snapshot-controller README with troubleshooting guidance for CrashLoopBackOff issues and update kustomization.yaml to include deployment patch. This improves user experience and deployment reliability.

clusters/noble/bootstrap/csi-snapshot-controller/controller/deployment-patch.yaml

@@ -0,0 +1,19 @@
+# Overlay on upstream setup-snapshot-controller.yaml (external-snapshotter v8.5.0).
+# - We only install GA VolumeSnapshot CRDs (no VolumeGroupSnapshot*). Explicitly disable the
+#   group-snapshot feature so the controller does not wait on / watch APIs we did not install.
+# - Longer CRD wait helps apiserver/etcd under load during bootstrap (avoids startup timeout).
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: snapshot-controller
+  namespace: kube-system
+spec:
+  template:
+    spec:
+      containers:
+        - name: snapshot-controller
+          args:
+            - "--v=5"
+            - "--leader-election=true"
+            - "--feature-gates=CSIVolumeGroupSnapshot=false"
+            - "--retry-crd-interval-max=5m"