v4 Format Support

[XAce1337manX]

Features:

• Can edit v4 maps - Mainly for compatibility with official editor
• Saving with incompatible data in format will prompt a warning
• Additions to Song Info screen to support new fields
  • Vanilla:
    • Mappers, lighters, and shared lightshow fields
    • Environment selection per diff
  • Custom:
    • Read support for custom characteristics
    • Stub wip menu for new SongCore features (lets users know the feature exists)
    • Small UX improvements to pop up menus (rewording and closing)

SongCore custom characteristic display	Environment Removal moved into Custom Properties menu

(If any one wants to offer suggestions to the menu, feel free)

Brief overview of changes:

• BeatSaberSong replaced with BaseInfo. Reading to and writing from this is handled in V2Info and V4Info
  • A majority of changes will be just changing this reference
  • V4 classes, as with V2 and V3, just handle IO
• New maps are created with v4 info as it gives access to some new metadata fields and still supports difficulties of any version.
• New difficulties are still created in v3 as CustomJSONData does not have a specification for v4. For now, v4 custom properties will display with v3 json in editor and will not persist on save

Lots of things to deal with. I expect to find more bugs when this gets merged.

[XAce1337manX]

Well. 1.40 just dropped with a bunch of map new features.

[Caeden117]

I don’t think the 1.40 additions to v4 blocks the PR. If you feel its ready for a dev merge, go for it, but I do totally understand if you want to ensure the latest features get added beforehand

[XAce1337manX]

Plans for this PR is probably:

• Merge after stable push - dev is in a stable state atm so I'm going to see if there's any bug fixes I can push to that before
• Add new fields to this PR so CM doesn't yeet them
  • No support in editor for this PR