[Bug] Wiicompiled `retro_rewind_root` (`Config.toml`) path is not respected

[matellush]

As detailed in #376 (review), some of the path handling seems to be broken currently. Not only is the NAND folder path handling still questionable with respect to the handling of (shared) Dolphin configurations due to validations and overridden NAND folders in Dolphin's config not being consistently applied, but the retro_rewind_root path in the Config.toml is not even registered as a setting in Wheel Wizard and thus never updated (unless I'm missing something).

For example, a shared Wiicompiled/Dolphin setup (with the toggle enabled) might have the launched Wiicompilation use the Wiicompiled-only paths for the license, while Wheel Wizard tries to use Dolphin's paths for displaying the licenses. If everything was properly synced (also the retro_rewind_root setting), then this should not happen.

[matellush]

It also seems like nand_root is not even updated in the Config.toml if Wheel Wizard's CT-MKWII directory is relocated.