New 3D plot types: parametric curves, parametric surfaces, implicit
surfaces, surface contours, and vector fields. New statistical plot
types: box, violin, pie/donut, and error bar charts. Two new template
notebooks for 3D plotting and statistics.

Bug fixes: parametric_surface argument count (9 not 10), implicit 3D
and vector field 3D performance (pre-allocated arrays instead of
endcons), pie chart reserved variable name. Added float() gotcha to
MCP AI instructions. Changed notebook extension to .macnb.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>