Implement tool remapping for MK4 / MMU3 using GCODE M863

[ruedli]

This text was provided as comment to issue #50 before, however it is a different topic, so I added it here.

The MK4 / MMU3 supports "tool remapping" in a menu of the MK4, before a print starts.

On octoprint this is not the case as far as I can see.

MK4 buddy board support M863 supports tool mapping GCODE, see https://help.prusa3d.com/article/buddy-firmware-specific-g-code-commands_633112

Explenation of GCODE M863:

M863 - Tool remapping
Allows to redefine which tools use for certain parts of the print.
If a part of an object is sliced to be printed with filament 1 - but you wish to print it with filament 2 instead, this G-code helps you achieve so.

Examples:

M863 M P0 L1 : Instead of tool 0, use tool 1
M863 E1/0 : Enable/disable tool remapping
M863 R : Reset tool remapping
M863 : Report current tool mapping

A menu to define such remapping (original tools, with the tool to select in a pulldown), would then issue appropriate M863 commands (starting with a reset and then setting them) as part of the startup commands.

M864 - Spool join settings

Note that a similar support could be used to define spooljoin features, see M864. Defining spooljoins other then the default "next spool" makes sense for multicolor prints and a MK4 / MMU3..

M864 - Spool join settings
Enables to configure Spool join function, defining which material to use after the one used runs out.

Examples:

M864 J A1 B2 : When tool 1 runs out of filament, continue with tool 2
M864 R : reset any settings
M864 : Report current spool join settings