maint(common): break long/slow running build configurations on TC into chained configurations

For example iOS builds often block for 20-30 minutes because of Apple servers.

From a [discussion on slack](https://keymanapp.slack.com/archives/C6Q9WS09G/p1745998203468599?thread_ts=1745994981.084919&cid=C6Q9WS09G) while discussing #13399:

_marc - Today at 09:30_
A secondary consideration is breaking down long/slow build configurations into chained configurations. For example, iOS, which often blocks for 20-30 minutes for Apple servers

It would be good to design for that even if we don't implement it just now

_eberhard - Today at 09:35_
How would chaining help? It still blocks a ba until Apple servers are done, or is there a way we can trigger the next link in the chain when the Apple servers are finished?

_marc - Today at 09:36_
yeah, we could build a trigger to continue the build -- and it would allow other builds in the queue to run in between

at worst, it can poll the server with a very quick run

I'm not all that keen on this, because it takes a single build log and splits it across multiple builds which is a lot harder to maintain. But worth consideration

_eberhard - Today at 09:42_
Ok, in our current, old setup chaining would be splitting a job in multiple jobs and adding the smarts to trigger the new jobs.