Expose forwarding related configuration data in ProxyConfig.

[kyngs]

Currently, the ProxyConfig interface does not expose anything related to player info forwarding. This is quite unfortunate if you need to access the forwarding mode (and secret) from your plugin. (For example, to send the secret to a built-in limbo).

The workaround to this issue is quite simple, import the velocity API implementation, cast the configuration to VelocityConfiguration, and then you can get the forwarding config. But, I believe that it is quite unfortunate to need to use the velocity API implementation directly.

[kyngs]

I've just looked into implementing this (as it seemed like a simple thing), but it appears the PlayerInfoForwarding enum is declared inside the velocity-proxy module and thus not available from the API module.
Moving the enum into the API module would cause incompatibilities with the plugins using it. (This should be defensible considering plugins should not use things from the proxy module, but I still don't want to break the plugins)

I'm kinda not sure what to do tbh

[hugmanrique]

Plugin authors know that everything in the proxy module is not subject to API versioning guarantees, and so may change at any moment. I doubt the list of plugins that depend on this enum is that long anyways.

[kyngs]

Mine for example does and this places me in a kinda awkward situation. Either I can use the internal module which will work for all versions of Velocity up before this got resolved, or I can use the new API which will only work on the latest versions

[hugmanrique]

There's ways to conditionally use one enum or another (for example, creating an interface in your plugin that abstracts the logic common to both enums and creating implementations in two different classes; making sure you don't load one or the other accidentally and using reflection to detect whether the Velocity instance provides this new feature in API). Still, your plugin depends on something that was never guaranteed to exist forever; the responsibility to fix this falls on plugin authors, not Velocity contributors.

[kyngs]

Fair ig, I'll just move the class into the api