Function prepareForModdingNewEngine

prepareForModdingNewEngine(
discovery: IDiscoveryResult,
api: IExtensionApi,
): Promise<void>
Prepares a new-engine Vampire Survivors installation for modding.

Detects whether MelonLoader and/or BepInEx are installed and:
- Warns if BepInEx 5 is installed, since it can't load mods for this IL2CPP game.
- Warns if no working loader is installed.
- Warns if both are installed and may conflict.
- Ensures the appropriate mods directory is writable for the active loader.
Parameters
- discovery: IDiscoveryResult
  The game discovery result from Vortex.
- api: IExtensionApi
  Vortex extension API.
Returns Promise<void>
- Defined in setup/newEngine.ts:19