Fix more broken links, add lazy-loading to images

manuscript/docker-swarm/traefik.md

@@ -11,7 +11,7 @@ There are some gaps to this approach though:
 
 To deal with these gaps, we need a front-end load-balancer, and in this design, that role is provided by [Traefik](https://traefik.io/).
 
-![Traefik Screenshot](../images/traefik.png)
+![Traefik Screenshot](../images/traefik.png){ loading=lazy }
 
 !!! tip
     In 2021, this recipe was updated for Traefik v2. There's really no reason to be using Traefikv1 anymore ;)
@@ -233,7 +233,7 @@ root@raphael:~#
 
 You should now be able to access[^1] your traefik instance on `https://traefik.<your domain\>` (*if your LetsEncrypt certificate is working*), or `http://<node IP\>:8080` (*if it's not*)- It'll look a little lonely currently (*below*), but we'll populate it as we add recipes :grin:
 
-![Screenshot of Traefik, post-launch](/images/traefik-post-launch.png)
+![Screenshot of Traefik, post-launch](/images/traefik-post-launch.png){ loading=lazy }
 
 ### Summary