This fixes a long-standing issue where 3D plots ignored scale transforms.
The methods set_xscale(), set_yscale(), set_zscale() existed but the
transforms were never applied to data or coordinates.

Key changes:

- axes3d.py: Add _get_scaled_limits() to transform axis limits through
  scale transforms. Modify get_proj() to use scaled limits for world
  transformation. Override _update_transScale() to use identity transforms
  since 3D projection handles scales internally. Update autoscale_view()
  and _set_lim3d() to apply margins in transformed space.

- art3d.py: Add _apply_scale_transforms() utility function. Update all
  do_3d_projection() methods to apply scale transforms before projection.

- axis3d.py: Update _get_coord_info() to return scaled-space bounds.
  Modify _draw_ticks() to transform tick locations to scaled space.
  Update draw() and draw_grid() for proper coordinate handling.

The fix ensures that:
- Data coordinates are transformed through scale transforms before
  projection (e.g., log10 for log scale)
- World transformation matrix maps scaled coordinates to unit cube
- Axis ticks, labels, and grid lines position correctly
- 2D display transforms remain linear (no double-transformation)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>