Add support for stack_max

[Sheriff-Unit-3]

Adds xcompat.functions.get_default_stack_max() which returns the current game's default stack size.

Includes documentation for utilities

[wsor4035]

Utilities is for internal only functionality. Hence it not being documented or supported. Additionally dunno if the current method will work with mod sec in other mods

[Sheriff-Unit-3]

Ok thanks for the info on utilities, removed the utilities documentation and moved get_stack_max() to functions. I don't know of any mods that change the default stack_max, but it wouldn't be to hard to change the function to support them.

[SwissalpS]

Shouldn't the function be called get_default_stack_max? From the current name I was expecting an itemname passed as argument - not that such a function would make much sense in xcompat scope.

[SwissalpS]

Shouldn't the function first check if the server settings have set a non-default default value for default_stack_max?
Return that if exists and fallback to the hardcoded values only if not existing.

[Sheriff-Unit-3]

Shouldn't the function first check if the server settings have set a non-default default value for default_stack_max?
Return that if exists and fallback to the hardcoded values only if not existing.

Well that's were it gets messy, so mineclonia manually sets the stack_max size to 64 for each of it's items/nodes, whereas minetest and many others just use the engine default (99). Therefore default_stack_max would work for minetest and some others, but wouldn't work for mineclonia.

Another thing to consider is Exile has 3 different default stack_max's: https://codeberg.org/Mantar/Exile/src/branch/master/mods/exile_game/init.lua#L3-L5

[SwissalpS]

Shouldn't the function first check if the server settings have set a non-default default value for default_stack_max?
Return that if exists and fallback to the hardcoded values only if not existing.

Well that's were it gets messy, so mineclonia manually sets the stack_max size to 64 for each of it's items/nodes, whereas minetest and many others just use the engine default (99). Therefore default_stack_max would work for minetest and some others, but wouldn't work for mineclonia.

In that case mineclonia needs to be treated separately. A server based on MTG can still set the default to something else and the current state of this new function wouldn't catch that.

[Sheriff-Unit-3]

Addressed @SwissalpS comments. The function now takes into account if the game currently running uses the engine setting/default or sets it's own.