Return estimated remaining_length in addtion to remaining_weight

[akonkol]

I am looking to grab the filament required for a print and see if that amount is available on the active spool. If there is not enough filament on the spool to satisfy the print I want to throw an error in the UI or return something like a 409 (which may be more complex).

The amount filament required for a gcode file can be found via a call to /server/files/metadata?filename={filename}. The value provided by the slicer is provided in millimeters

Although you could leave it up to the developer to create a helper function as you done here I think it would be nice if Get Spool returned remaining_length as well as remaining_weight

[Donkie]

Good idea, this is an easy addition