Geometry Nodes: Accumulate Fields Node

This function node creates a running total of a given Vector, Float, or
Int field.

Inputs:
  - Value: The field to be accumulated
  - Group Index: The values of this input are used to aggregate the input
    into separate 'bins', creating multiple accumulations.
Outputs:
  - Leading and Trailing: Returns the running totals starting
   at either the first value of each accumulations or 0 respectively.
  - Total: Returns the total accumulation at all positions of the field.

There's currently plenty of duplicate work happening when multiple outputs
are used that could be optimized by a future refactor to field inputs.

Differential Revision: https://developer.blender.org/D12743

release/scripts/startup/nodeitems_builtins.py

@@ -753,6 +753,7 @@ geometry_node_categories = [
         NodeItem("GeometryNodeImageTexture"),
     ]),
     GeometryNodeCategory("GEO_UTILITIES", "Utilities", items=[
+        NodeItem("GeometryNodeAccumulateField"),
         NodeItem("ShaderNodeMapRange"),
         NodeItem("ShaderNodeFloatCurve"),
         NodeItem("ShaderNodeClamp"),