Smooth timelapse no longer charges a prime volume it does not purge. A
tower printed with no tool change is exactly the idle depth: the
stability minimum for Type2, the wrapping detection depth for Type1.
Charging a full prime_volume on top made the previewed and arranged
tower deeper than the one that is printed.
The Type2 half of "a tool change reserves a tower whatever the purge
volumes resolve to" arrives with the base commit; here it only has to
survive the planner split, since Type1 already reserves per filament.
The wipe tower filament only joins the tool ordering when there is a
tower to join, which is the has_wipe_tower() half of the guard
Print::extruders applies.
Hanif Koh
2fdc16f9f2