Option for "Editor Tag" on Files/Folders

[OrderX8]

Add an option in the FilesSystem to tag files or folders as "only used in the editor".
This makes it easier to exclude unneeded files and folders in the game's build.

[timothyqiu]

Maybe we can reuse the coloring system and add an option in the export preset dialog to exclude folders in a certain color :P

[lucastucious]

Could be nice to prevent unwanted files in build, in case of unwanted links when you build with "dependencies" enabled.

Like a warning/error if "editor only" files are bundled or want to be bundled