fix(vispy): use proximal and distal radii for mesh

During refactoring, we'd used only the one radii, but that meant we only
got cylinders, not cones and other related shapes where the two radii
can be different.

Note that this means there may be more unique meshes, and so, the
precision may be reduced more by the heuristic. But, it will allow users
with more computing power to get more accurate meshes.

Author: sanjayankur31

pyneuroml/plot/PlotMorphologyVispy.py

@@ -724,10 +724,11 @@ def plot_3D_cell_morphology(
         length = cell.get_segment_length(seg.id)
 
         # round up to precision
-        r = round(p.diameter / 2, mesh_precision)
+        r1 = round(p.diameter / 2, mesh_precision)
+        r2 = round(d.diameter / 2, mesh_precision)
         key = (
-            f"{r:.{mesh_precision}f}",
-            f"{r:.{mesh_precision}f}",
+            f"{r1:.{mesh_precision}f}",
+            f"{r2:.{mesh_precision}f}",
             f"{round(length, mesh_precision):.{mesh_precision}f}",
         )