feat: Remote mods directory

[Alystrasz]

This pull request introduces remote mods folder, located at /runtime/remote/mods, that will store future auto-installed mods.

In short, it's the "mods need to pull from 2 folders, local (user-installed) and remote (auto-installed)" mentioned by @BobTheBob9 in #396.

Changes

• Creates remote mod directory if it does not exist;
• When loading mods, check local folder AND remote mod folder

(note: there was already a REMOTE_MOD_FOLDER_SUFFIX variable in code, I simply added some stuff around to use it)

[BobTheBob9]

looks great and shouldn't create any different behaviour between the different mod dirs due to how we store mods at runtime