This commit moves the code for the resample curves node to the
geometry module, to allow reusing it in any editor. The same options
are available, accessible with the `ctrl-R` shortcut like mesh sculpt
mode.
I also refactored the inputs and outputs of the resample code to use
`CurvesGeometry` rather than geometry components. Ideally this would
make it a bit more general and a bit simpler. However, currently this
requires some hacks to use the attribute API. After future refactors
to separate the attribute API from `GeometryComponent`, that
part will get simpler.