Add JSON schema generation for kubeconform CRD validation

- ci/generate-schemas.sh generates schemas from CRD manifests and K8s swagger
- Sources: ArgoCD v3.3.2, Gateway API v1.5.1, Kubernetes v1.33.7
- Optionally fetches live cluster CRDs via kubectl when available
- Generated schemas committed to schemas/ for CI use
- Run `make schemas` to regenerate after CRD version bumps
- validate-apps.sh and validate-clusters.sh check local schemas first

schemas/replicationcontrollerlist_v1.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "additionalProperties": true,
+  "properties": {
+    "apiVersion": {
+      "type": "string"
+    },
+    "items": {
+      "items": {
+        "$ref": "#/definitions/io.k8s.api.core.v1.ReplicationController"
+      },
+      "type": "array"
+    },
+    "kind": {
+      "type": "string"
+    },
+    "metadata": {
+      "additionalProperties": true,
+      "type": "object"
+    }
+  },
+  "type": "object"
+}