Engineering

These minibots need designing as replicable units

If you make a factory unit that churns out minibots then you have to scale the factory unit when you need to scale the minibots. So it's the factory unit which is self-replicating. That seems okay. If the factory unit is made of minibots then that's how the minibots replicate themselves but both aspects need designing. One minibot can't make a new minibot but lots of minibots can combine to make a minibot factory.

Minimizing the number of specialist minibots seems sensible. On the other hand if some are construction parts and some are processing parts and some are bot team long-range communication parts, that could be three specialisms immediately.

The bot factory has to be able to construct logic circuitry. Silicon chips. Capacitor/batteries fed from the eternal energy feed. Every bot has at least this close-coupling communications chip so they can self-organize.

Every bot has to be mobile. The site bots are in a gravity well, the mirror bots aren't, that's two forms of mobility.

Mining

What the landing fab has to be able to build from scratch is a mining site able to replicate with local materials. The planning model for that will be exciting.