feat: C2SModAPIConnect

Author: RedVortexDev

src/main/java/com/mcdiamondfire/proto/ModAPIMessages.java

@@ -43,6 +43,7 @@ public final class ModAPIMessages {
 
 		// Player.
 		registerMessage(C2SPlayerTeleport.class, "c2s_player_teleport");
+		registerMessage(C2SModAPIConnect.class, "mc2s_modapi_connect");
 
 	}
 

src/main/proto/serverbound_player.proto

@@ -9,3 +9,10 @@ option java_multiple_files = true;
 message C2SPlayerTeleport {
 	WorldLocation location = 1; // The location to teleport to.
 }
+
+// Notifies the server you are interested in receiving ModAPI messages.
+// This must be sent before any ModAPI messages are sent by the client.
+// If the protocol versions are major version incompatible, the request will be voided.
+message C2SModAPIConnect {
+	string protocol_version = 1; // The version of the protocol the client is using.
+}