feat: add runner conversion scripts and strengthen cutover automation

setup/pi-monitoring/portainer-agent.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+ set -euo pipefail
+ 
+ docker run -d \
+  -p 9001:9001 \
+  --name portainer_agent \
+  --restart=always \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  -v /var/lib/docker/volumes:/var/lib/docker/volumes \
+  -v /:/host \
+  portainer/agent:2.39.0