Remove call invokers

[WyriHaximus]

Initially these call invokers where added to keep ext-eio under control. And they made sense in the design for that adapter. But with uv adapter coming up this feels less and less like it makes sense due to the increased overhead caused by it.

[WyriHaximus]

Ping @clue @CharlotteDunois what do you think?

[clue]

Makes perfect sense! I understand where they're coming from, but I agree that they feel more like a burden than actually helping with implementing new features in the current state 👍

[WyriHaximus]

I'll get onto it 👍