[DX] Allow more granulated return type completion, to separate from closures and makes easier to review about rector HOT 3 CLOSED

ClosureReturnTypeRector can be added, and register after other closure return types rules so executed on last

from rector.

Looking into this.

At the moment we have single AddArrowFunctionReturnTypeRector to handle these cases. I think it makes sense, as in the wild there is hundreds of methods/functions, but much less callbacks/arrow functions. So it's easier to review these cases without granulation.

We can introduce possibly single rule, e.g. ClosureReturnTypeRector to handle such cases. That would keep ClassMethod and Fuction_ rules separated, and easier to add types to closure on separete Rector run :)

from rector.

@samsonasik That's the plan. void and never are the easy ones to pick

from rector.