doc: add agent registration instructions

- add section on how to get existing server token
- add steps to create a new token
- add instructions on how to register an agent/worker

🤖

README.md

@@ -18,6 +18,29 @@
 
 `docker compose exec -it k3s kubectl config view --flatten`
 
+### Add Agents
+
+#### Get Agent Token
+
+> The secure token format (occasionally referred to as a "full" token) contains the following parts:
+> 
+> <prefix><cluster CA hash>::<credentials>
+
+Get existing server token:
+`cat /var/lib/docker/volumes/baseline_k3s-data/_data/server/token`
+
+Create new token:
+`docker compose exec -it k3s k3s token create`
+
+#### Register Agent/Worker
+
+```bash
+export K3S_URL=https://<cpn.fqdn>:6443
+export K3S_NODE_NAME=<node.fqdn>
+export K3S_TOKEN=<full-token>
+curl -sfL https://get.k3s.io | sh -s -
+```
+
 ## Notes
 
 ### ArgoCD
@@ -41,7 +64,6 @@ operation:
 
 See: [infrastructure/zabbix-config - Zabbix Kubernetes Monitoring](https://git.smsvc.net/infrastructure/zabbix-config/src/branch/master/Zabbix-Kubernetes.md)
 
-
 ## Cloud Setups
 
 ### Linode