1. convert instance to object when loading previous 3mf
2. fix an exception issue caused by previous commit caused by nil value of import_project_action
Change-Id: Ieed853f0e8d458aab1716acf52307c5d672ebe22
Add custom gcode back, which can be inserted in
gcode viewer layer slider.
Signed-off-by: salt.wei <salt.wei@bambulab.com>
Change-Id: I270cc438bedf11b30f07f8f9bad6ae5436d5a2dd