It's not a problem for most ships given they'll likely be compatible with yards.
For repair purposes, all you need is a slipway with sufficient tonnage capacity. It doesn't matter whether it's naval or commercial.
Which I wrote in my reply to Narmio's question about repairing habs.
However, if the ship with armor damage is several jumps and or months away from the shipyards, another way to repair armor would be useful.
Do you now have that ship as a class in your ship design screen?
If so, back up your database and then go to that design and put in a pile of engineering bays plus maintenance holds then SM it's maintenance supplies to full and see if you can then repair it using the onboard mechanisms.
Just be careful though, changing the design may have knock on effects.
I've already destroyed it. I also wasn't able to recapture after killing off all the crew.
As both of you seem to think otherwise, let me be clear: I have no desire to repair any part of any orbital habitats.