feat: Move cluster services to wild-directory as unified packages

Convert all 15 cluster services from embedded API format to
wild-directory packages using the unified manifest format:
- metallb, traefik, cert-manager, longhorn, snapshot-controller
- nfs, smtp, coredns, node-feature-discovery, nvidia-device-plugin
- externaldns, docker-registry, headlamp, crowdsec, utils

Changes:
- wild-manifest.yaml → manifest.yaml with is, defaultConfig, requires
- Eliminated configReferences and serviceConfig fields
- Flattened kustomize.template/ to package root
- Template vars use flat defaultConfig keys
- install.sh paths updated for apps/ layout
- Updated 9 app manifests: cloud.smtp.* → apps.smtp.* with requires
- Removed dead install: true field from 6 app manifests

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

coredns/install.sh

@@ -0,0 +1,50 @@
+#!/bin/bash
+set -e
+set -o pipefail
+
+if [ -z "${WILD_INSTANCE}" ]; then
+    echo "ERROR: WILD_INSTANCE is not set"
+    exit 1
+fi
+
+if [ -z "${WILD_API_DATA_DIR}" ]; then
+    echo "ERROR: WILD_API_DATA_DIR is not set"
+    exit 1
+fi
+
+if [ -z "${KUBECONFIG}" ]; then
+    echo "ERROR: KUBECONFIG is not set"
+    exit 1
+fi
+
+INSTANCE_DIR="${WILD_API_DATA_DIR}/instances/${WILD_INSTANCE}"
+COREDNS_DIR="${INSTANCE_DIR}/apps/coredns"
+
+echo "=== Setting up CoreDNS ==="
+echo ""
+
+echo "Using pre-compiled CoreDNS templates..."
+if [ ! -f "${COREDNS_DIR}/kustomization.yaml" ]; then
+    echo "ERROR: Compiled templates not found at ${COREDNS_DIR}"
+    echo "Templates should be compiled before deployment."
+    exit 1
+fi
+
+echo "Applying CoreDNS custom override configuration..."
+kubectl apply -k "${COREDNS_DIR}/"
+
+echo "Restarting CoreDNS pods to apply changes..."
+kubectl rollout restart deployment/coredns -n kube-system
+echo "Waiting for CoreDNS rollout to complete..."
+kubectl rollout status deployment/coredns -n kube-system
+
+echo ""
+echo "CoreDNS configured successfully"
+echo ""
+echo "To verify the installation:"
+echo "  kubectl get pods -n kube-system -l k8s-app=kube-dns"
+echo "  kubectl get svc -n kube-system coredns"
+echo "  kubectl describe svc -n kube-system coredns"
+echo ""
+echo "To view CoreDNS logs:"
+echo "  kubectl logs -n kube-system -l k8s-app=kube-dns -f"