Custom client name on socket connections

[holasoyender]

This pull requests adds support for setting a custom Client-Name header when connecting to a Lavalink node.

Example code

// Create a LavalinkClient with the default client name (`Lavalink-Client/<VERSION>`)
..
final LavalinkClient client = new LavalinkClient(Helpers.getUserIdFromToken(token));
..

// Create a LavalinkClient with a custom client name
..
final LavalinkClient client = new LavalinkClient(Helpers.getUserIdFromToken(token), "TestBot");
..

Why?

In the case of multiple bots connecting to the same Lavalink node, it can be useful to identify each bot by a name, and not the library that they are using

Example with the current library

lavalink: 2025-03-05T15:17:25.859Z  INFO 1 --- [Lavalink] [  XNIO-1 task-2] lavalink.server.io.SocketServer          : Connection successfully established from Lavalink-Client/3.2.0
lavalink: 2025-03-05T15:17:26.453Z  INFO 1 --- [Lavalink] [  XNIO-1 task-2] lavalink.server.io.SocketServer          : Connection successfully established from Lavalink-Client/3.2.0
lavalink: 2025-03-05T15:17:27.129Z  INFO 1 --- [Lavalink] [  XNIO-1 task-2] lavalink.server.io.SocketServer          : Connection successfully established from Lavalink-Client/3.2.0

Example with custom client name(s)

lavalink: 2025-03-05T15:17:25.859Z  INFO 1 --- [Lavalink] [  XNIO-1 task-2] lavalink.server.io.SocketServer          : Connection successfully established from TestBot1
lavalink: 2025-03-05T15:17:26.453Z  INFO 1 --- [Lavalink] [  XNIO-1 task-2] lavalink.server.io.SocketServer          : Connection successfully established from TestBot2
lavalink: 2025-03-05T15:17:27.129Z  INFO 1 --- [Lavalink] [  XNIO-1 task-2] lavalink.server.io.SocketServer          : Connection successfully established from TestBot3

[duncte123]

Unfortunately this is disallowed per the lavalink documentation: https://lavalink.dev/api/websocket.html

[holasoyender]

Could be possible to implement it using the lavalink documentation? For example

final LavalinkClient client = new LavalinkClient(Helpers.getUserIdFromToken(token), "TestBot");

would connect with the Client-Name header TestBot-LavaLink-Client/<VERSION> or similar, like TestBot-(LavaLink-Client)/<VERSION>