Batching modifications and resizing channels

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currently, the API for Mesh.Collection<T> increments the version of the mesh whenever any of this functions are used, or properties or indexers. in the case of doing the following every frame, it's very inefficient:

float x = MathF.Sin(time);
float y = MathF.Cos(time);
Mesh.Collection<Vector3> positions = mesh.GetPositions();
positions[0] = new(x + 0, y + 0, 0);
positions[1] = new(x + 1, y + 0, 0);
positions[2] = new(x + 1, y + 1, 0);
positions[3] = new(x + 0, y + 1, 0);

when instead it could be chunked. not sure how exactly, but perhaps this could be done by fetching a temporary view of the mesh, updating that then submitting it:

Mesh mesh = ...
Mesh.Modification changes = mesh.BeginChanges();
changes[0].position = new(x + 0, y + 0, 0);
changes[1].position = new(x + 1, y + 0, 0);
changes[2].position = new(x + 1, y + 1, 0);
changes[3].position = new(x + 0, y + 1, 0);
mesh.SubmitChanges(changes);

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the needed set of requirements for this and in general:

• not being allowed to create different lengths of channel data
  • should not be possible to create 32 vertex positions, but only 5 vertex colors

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update title because as of right now, there is no exposed way through a Mesh to resize a channel. and its bulked into this issue because the work towards batching modifications should cover this need.