Lift tool before tool change to avoid material contamination.

[alchitry]

When using my XL 5H, I've been having a hard time getting good wipe-tower free prints.

When changing a tool without a wipe tower, the printer currently just stops while touching the print and does the tool change. The tool change then returns to where it was but that causes colors to be contaminated.

It then rapids to the next location without a lift dragging the nozzle across the last layer.

This change lifts the tool right before the change and returns it down before the next extrude.

This should fix #12694

[alchitry]

The second commit improved the original by making the tool change happen after the rapid to the next spot but before lowering down.

This keeps any colors from contaminating each other but also keeps any oozing when a new tool heats up over the correct color.