docs: show the full section both ways in as_points

Open the speed section with the entire 167780-cell section rendered as
full geometry and as as_points, coloured by EPCAM. Previously the full
dataset only appeared as as_points in the backend section; the
full-geometry vs as_points comparison was limited to the crop.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: timtreis