Add `nodes` to the generated `talosconfig` file

[budimanjojo]

Ref: #344 (comment)

Aside from adding controlplane nodes IP addresses to the contexts.<context>.endpoints in the generated talosconfig, should also maybe add all nodes IP addresses to the contexts.<context>.nodes too.

This is something that I personally do in my talosconfig and I can't remember any reason why I didn't do it in talhelper although I did decided to not do this in the end.

This is what I found so far about having it inside talosconfig in the official docs (https://www.talos.dev/v1.6/learn-more/talosctl/#endpoints-and-nodes):

The node is the target node on which you wish to perform the API call. While you can configure the target node (or even set of target nodes) inside the ’talosctl’ configuration file, it is recommended not to do so, but to explicitly declare the target node(s) using the -n or --nodes command-line parameter.

[onedr0p]

Thanks!