Add heating_radius to HeatEnergySource

[Thremtopod]

It can feel a bit silly to have an entity with glowing-hot heat pipe attachment points not be able to heat neighboring entities. When entities have multiple heat connections they can act like heat pipes (i.e. heat can flow through them), which makes the lack of heating_radius more noticeable.

Screenshot_20260407_010152.png (1.09 MiB) Viewed 376 times

Screenshot_20260407_010229.png (1014.71 KiB) Viewed 376 times

[protocol_1903]

+1

[Kryzeth]

+1

I could really use this for heat inserters, instead of relying on hidden heat pipes (and soon, hidden heat interfaces, since my previous hidden heat pipe workaround no longer seems to work in 2.1)

[AndreusAxolotl]

+1