API to allow addons to interact with the Steam Boiler

[ChiefArug]

At the moment it is incredibly hardcoded, like doing instanceof checks against the steam engine class and having numbers for 'consumption' hardcoded.

A way for addons to add new sources of steam (not just water or heat, but both together), and a way for addons to add blocks that 'consume' steam from the boiler would be two core components I would like to see.

One method of doing this is making steam an actual fluid, but this goes against Create's general design so is not worth considering much.

At its simplest form replacing the instanceof SteamEngine calls with an interface, and having that interface allow returning how much steam is 'consumed' from the boiler for that block (probably in units of SU, or whatever the steam engines currently use as units) would be adequate for this, but a more in depth solution would be desireable, such as using (Neo)Forges capability system, although I understand that would make it harder for the Farbic team to port.

Conversation in Discord that sparked this issue: https://discord.com/channels/620934202875183104/706162751642533909/1239425143130947675