Widget networking

[Juuxel]

• Two widget packet types:
  • libgui:clientbound_widget_update
    • Structure: syncId: VarInt, widgetId: String, contents: Buf
  • libgui:serverbound_widget_update
    • Structure: syncId: VarInt, widgetId: String, contents: Buf
• All networking widgets must have a unique ID of some sort (either a string or an identifier). This can be shared with styles (Styling #60).
• Only widgets with a synced host can send messages, so hook networking up to validate or createPeers.
• Example API:

  @Override
  public void validate(GuiDescription host) {
      super.validate(host);
      host.registerWidgetMessageHandler(this, MessageType.S2C, buf -> { /* handle the message */ });
  }
  
  @Override
  public void tick() {
      if (host.isServer()) host.sendWidgetMessage(this, MessageType.S2C, buf -> buf.writeString("hello"));
  }

[Juuxel]

Closed by a608419 and 788176d.