Add Area and Centroid nodes (#1749)

* initial attempt for area node

* allow node preview for more types

* make AreaNode sync and add CentroidNode

* cargo fmt

* preview of DVec2

* make the nodes async again

* use segment domain instead of region domain

* modify the check for linearity

* create a limit for area in centroid calculation

* cargo fmt

* reverse unnecessary changes

* add threshold to area calculation too.

* handle zero area edge case

* add todo comment

* implement 1D centroid and use it as fallback

* formatting floats to skip last zero

* add Centroid Type radio button to Centroid Node

* rename docs to use area and perimeter centroid

* add web demos for perimeter centroid

* add tests for perimeter centroid

* add fallback to use average of points

* Fix for broken area

* missing fixes

* Code review and rename Perimeter Centroid to Length Centroid

* Use dummy footprint in Area and Centroid nodes

* add doc and todo to clarify when `is_linear` fails

* use epsilon instead of zero

---------

Co-authored-by: 0hypercube <0hypercube@gmail.com>
Co-authored-by: Keavon Chambers <keavon@keavon.com>
Co-authored-by: Dennis Kobert <dennis@kobert.dev>

node-graph/gcore/src/graphic_element/renderer.rs

@@ -595,6 +595,7 @@ impl Primitive for String {}
 impl Primitive for bool {}
 impl Primitive for f32 {}
 impl Primitive for f64 {}
+impl Primitive for DVec2 {}
 
 fn text_attributes(attributes: &mut SvgRenderAttrs) {
 	attributes.push("fill", "white");