Convert to Smooth or Corner on a blend whose spine came from Replace
Spine stored key anchors with the converted spine, so the spine's
points then moved onto the key centers. It now changes only the
spine's handles: the points stay where they are and the keys stay
spread along the spine. Direct Selection's spine conversion and the
other spine edits are unchanged.
With a blend selected, the Contextual Task Bar's Corner and Smooth
buttons failed with "select paths or anchor points", since
`path.convertAnchors` only read paths. They now convert every point of
the blend's spine, as they convert every anchor of a path selected
whole, in one undo step. The key objects stay where they are.
With Direct Selection, the Control bar and the Properties panel now
show their Convert buttons for a selected blend too.
dotCooCoo