Add Talos upgrade and system extensions documentation

- Add comprehensive UPGRADES-AND-EXTENSIONS.md guide covering:
  - System extensions via schematics and Image Factory
  - Talos version upgrade procedures (control plane + workers)
  - Kubernetes version upgrades
  - Rolling upgrade best practices
  - Troubleshooting common upgrade issues
- Add rolling-upgrade-workers.sh script for automated worker upgrades
- Includes safe wait times and confirmation prompts

talos/talhelper/rolling-upgrade-workers.sh

@@ -0,0 +1,66 @@
+#!/bin/bash
+# Rolling upgrade script for fastpass worker nodes
+# Usage: ./rolling-upgrade-workers.sh <image-url>
+# Example: ./rolling-upgrade-workers.sh factory.talos.dev/installer/abc123:v1.14.0
+
+set -e
+
+IMAGE="$1"
+if [ -z "$IMAGE" ]; then
+  echo "Usage: $0 <image-url>"
+  echo ""
+  echo "Example:"
+  echo "  $0 factory.talos.dev/installer/abc123def456:v1.14.0"
+  echo ""
+  echo "To get the image URL, run:"
+  echo "  cd /opt/git/homelab/talos/talhelper"
+  echo "  talhelper genconfig"
+  echo "  grep 'image:' clusterconfig/fastpass-jungle-cruise.yaml | head -1"
+  exit 1
+fi
+
+declare -A WORKERS=(
+  ["jungle-cruise"]="10.1.71.69"
+  ["haunted-mansion"]="10.1.71.70"
+  ["peter-pans-flight"]="10.1.71.71"
+)
+
+echo "=========================================="
+echo "Rolling Worker Upgrade"
+echo "=========================================="
+echo "Image: $IMAGE"
+echo "Workers: ${!WORKERS[@]}"
+echo ""
+read -p "Proceed with rolling upgrade? (y/N): " -n 1 -r
+echo
+if [[ ! $REPLY =~ ^[Yy]$ ]]; then
+  echo "Aborted."
+  exit 0
+fi
+
+for worker in jungle-cruise haunted-mansion peter-pans-flight; do
+  ip="${WORKERS[$worker]}"
+  echo ""
+  echo "=========================================="
+  echo "Upgrading $worker ($ip)..."
+  echo "=========================================="
+  
+  talosctl upgrade --nodes ${ip} --image ${IMAGE} --preserve
+  
+  echo "Waiting for $worker to be Ready..."
+  kubectl wait --for=condition=Ready node/${worker} --timeout=10m
+  
+  echo "✓ $worker upgrade complete."
+  
+  if [ "$worker" != "peter-pans-flight" ]; then
+    echo "Sleeping 30s before next node..."
+    sleep 30
+  fi
+done
+
+echo ""
+echo "=========================================="
+echo "✓ All workers upgraded successfully!"
+echo "=========================================="
+echo ""
+kubectl get nodes -o wide