]SGC, I believe the answer to your question lies in the Ancients shown and, proven ability to create artificial intelligence and interface with it...Like Replicators or the â€œchairâ€ device (both Destiny and Atlantis versions).
Remember the episode in SGA when the wraith scientist successfully interfaced with that Ancient warship, Aurora, I think?? How about when Rush discovered the ships bridge and was communicating with both Franklin and his wife on separate occasions...Well, was he hallucinating or actually interacting with the Destinyâ€™s artificial intelligence/consciousness?? By the way, remember in season 2 episode â€œSabotageâ€ when Franklin sits in the chair then disappears...Where did he go? Whoâ€™s to say his consciousness isnâ€™t alive and well somewhere within the ships intelligence (Remember Thor did it in SG-1 episode â€œDescentâ€).
If we all remember the SGU season 1 episodes â€œFaithâ€ and then â€œSabotage,â€ the team discovered those mechanical, spider like drones. They even put them to work in repairing the ships â€œFTLâ€ drives as well. What if these drones transported to a planetâ€™s surface somehow, then mined the materials? I mean, just look at the roverâ€™s humanity is currently sending to Mars...Which bring back samples of rock and Martian surface material the like. Just look at how the SG-1 replicator's were able to consume raw materials, like Asgard ships, then literally produced more replicators. So, these drones probably â€œmineâ€ but, how do the stargates get manufactured??
Well, remember in the SG-1 episode â€œNew Orderâ€ when Thor was able to synthesize the anti-replicator weapon ala Star Trek â€œreplicatorâ€ style...I donâ€™t know about you, but the cargo room onboard the seeder ship looked the size o' warehouse or of an airplane hangar...It had dozens of orders of stargates completed, and ready for deployment.
Look, all Iâ€™m suggesting is that just maybe the Seeder ships and Destiny are a lot more intelligent than we know? Thor was able to synthesize the weapon with the Ancients knowledge, so itâ€™s logical to assume that as long as the material is available and mined, then both the ships "intelligenceâ€ and technology are surely capable in manufacturing and, seeding stragates, yes?!