New build --stop-after

[mosteo]

This allows stopping the build process at different points, which may help in debugging actions, ensuring up-to-date config without requiring updating dependencies nor building, etc.

Fixes #1544

[Fabien-Chouteau]

Maybe explain when this could be useful. This is a debug tool, and people who are not experts may be in bad situations after using it.

[mosteo]

I added an explanation after the steps, and a clarification that a regular alr build should leave things as intended.

[Fabien-Chouteau]

This looks like a nice process for builds, but I see it is separate from how the code will run.
We may add new stages that will not be added to this enum, and vice versa.

Maybe we can have it more explicit with a loop like this:

for Stage in Build_Stages loop
   case Stage is
      when Sync =>
      when Generation =>
      
      -  Etc,
end loop;

[mosteo]

I think I understand what you mean, but not the implementation detail. What is that loop intended to replace?

Maybe the enum can be renamed to Stopping_Points as to make explicit what they are intended to be used for.

[Fabien-Chouteau]

Maybe that's an oversimplification of the build process on my part, and the different steps in the build are probably spread across different locations in the code.

Maybe the enum can be renamed to Stopping_Points as to make explicit what they are intended to be used for.

Indeed that would probably be better.

[mosteo]

Ah, I see. Yes, it's not as clear-cut as that, as there's some recursion involved through the dependency tree. I'll change the name then.