Sera airfab -> engineers are not selectable in the unloading process

Problem:

If you build an eng in a Sera airfab and the unit is finished, it takes a few seconds before the unit is "ready" to be selectable while it is getting unloaded from the fab.

Consequence:

In the seconds you need to wait, you already could have queued some orders. For example: Cybran eng can be instantly selected while it is unloading from its airfab.

Solution:

This game mechanic should be common for all races. The waiting time adds up over time and is just annoying. Let me select the eng when it is finished to give it some orders, so I can be busy somewhere else and forget about the eng.

In the future, better to make an issue on Github. Regardless, here's my first attempt at fixing it: https://github.com/FAForever/fa/pull/4253

It won't be what you'd expect.

A work of art is never finished, merely abandoned

@Jip Sprouto did the same/a very similar change for LOUD. You may want to look into that to compare against your implementation.

Thank you for the suggestion, I'll look at it 👍

A work of art is never finished, merely abandoned

@MostLostNoob just checked it, they do exactly the same thing but the (old) effects linger slightly longer.

A work of art is never finished, merely abandoned