feat: basic support for syncing custom files

[EchoEllet]

Allows to sync custom files, and remove them if they are no longer on the custom files list from the remote sync info file:

"customFileSyncInfo": {
    "deleteRemovedFiles": true,
    "files": [
      {
        "downloadUrl": "https://github.com/FreshKernel/kraft-sync/blob/main/sync-script/build.gradle.kts?raw=true",
        "filePath": "config/config.json"
      }
    ]
  }

The file path is not specific to the .minecraft directory although the current working directory is the same as the script executable, which is .minecraft (alongside the mods directory).

This project is no longer supported as it was as I'm not very motivated to work on it, and I will only post simple changes to fit some requirements without maintenance or quality updates.