[Blueprints, 02-at-scale]: Windows Builds Nodes: Clarifications on Launching times

[carlosrodlop]

Some colleagues expressed their concerns about including Windows K8s workers nodes within the At scale Blueprints as current best practices.

I spent time investigating on this topic concluding the following points (which are included in this PR):

• It is known that Linux container lunch times are faster than Windows container. That reality can be improved by using a cache container image strategy (see Speeding up Windows container launch times with EC2 Image builder and image cache strategy and more about Windows Container Best Practices)
• It is not accurate to say that K8s Windows Node Pools never will be a recommended option for any customers. Currently, there are CloudBees customers using Windows K8s container Nodes, including CloudBees (link - internal) Jenkins Community (link). Other interesting thread here https://www.reddit.com/r/kubernetes/comments/13uj9pt/anyone_running_windows_nodes_in_your_clusters/
• Alternatively to Windows K8s workers nodes, Windows VM can be used via Shared Agents. Separate VM will reduce the provisioning time but lacks of other native advantages of running build into a K8s environment like (e.g. resiliency, autoscaling, integrated observability with the cluster).