Eros Server Handler

### V3 — Direct Server-to-Server Routing & Config Overhaul

This is a major architecture update that enables true direct server-to-server transfers without forcing players to pass through the lobby, while keeping all security checks fully enforced.

Core changes:
- Players can move directly between backend servers (vanilla, sb, minigames, etc).
- Server switching no longer requires an automatic lobby hop.
- Direct client connections to non-lobby servers are still blocked.
- Shared secret validation remains mandatory for every transfer.
- Only servers defined in the configuration are trusted.

Config.yml changes:
- server.name identifies the current server and must be unique per server.
- server.secretKey is a shared security key and must be exactly the same on all servers.
- trustedSource defines the main entry server, usually the lobby.
- Direct player connections are only allowed on the trustedSource server.
- Backend servers will continue to reject direct joins.
- servers acts as a network-wide internal whitelist.
- The servers list must be identical on every server for direct routing to work.

Command behavior:
- Server jump commands such as /vanilla or /sb are available on all servers.
- Commands connect players directly to the target server.

Important notes:
- Configuration reload is not supported.
- A full server restart is required after any configuration change.
- Incorrect host, port, or secret configuration will break server transfers.

This update significantly improves routing flexibility and scalability while preserving strict security guarantees.