Allow a heat source to melt ice

[Tend]

There are 2 ways to generate power in factorio: solar and steam-based.
On Aquilo you have plenty of ice but no steam, and the only way to get water from ice to then get steam is to have electricity in a chemical plant. This requires you to build a solar panel, which feels entirely against how Aquilo is meant to work given the 99% reduction.

I think it would be good to have a way to use heat to melt ice. Whether that's a new building that takes heat pipes in, or just the existing heat exchangers being allowed to take ice instead of (or in addition to) water.

A couple ways this could be implemented:
- heat exchangers take one or both of ice and water and always output steam (heat cost is increased if ice is input)
- heat exchangers have two recipes, ice to water or water to steam

This would make starting on Aquilo much easier/faster and more thematic. If also just makes sense for it to be possible.

It may also be useful on space platforms to prevent you getting deadlocked on a nuclear powered platform that runs out of ice temporarily and so runs out of water and therefore power. Restarting this platform is hard because you can't separate the electrical networks to prioritise the ice melting chemical plants and asteroid grabbers. This would allow an emergency fuel-based solution to kick-starting nuclear again.

[Voxera]

Would not require a new building.

Either use the normal assembler which already can have a fluid output when emptying barrels and allow that to also have a heat pipe input, or use the chem plant and allow it to have a heat pipe input and then add a recipe for Ice to water that requires heat.

And I agree, forcing you to have solar to get that first water or having to bring barreled water to get started feels very off.