Magnification doesn't work on Paths

Path/Node/Segment/Style transformations just change initial point, angle, and handedness. So right now magnification (e.g. `2*pa` or `magnify(pa, 2)`) just affects the initial point. The result of magnifying a path then rendering it should be the same as rendering it then magnifying the resulting polygons. (Right now Styles don't see any transformation except for handedness changes, and those I think only for DecoratedStyle.)

This has never come up as far as I know because magnification is basically never used.

Trace how transformations are applied across Path, Node, Segment, and Style, then follow the rendering flow. Compare magnifying a path before rendering with magnifying the rendered polygons afterward; done means both results are equivalent, including style transformations.

Written by the indexing model from the issue text.