Add ability to create buttons and menu's on title screen

Status
Fixed
Issue description

Add ability to create custom buttons and menu's on title screen.

i have plans for a future bug filled joke mod that will be a joke of sorts that causes all kinds of random chaos in funny weird ways that increases in frequency and makes a mess of and eventually corrupts the players world once the first part of it is triggered by placing a single block that begins the chaos.

i want to make a menu that if the mod was installed, before the title screen even comes up, it has a message come up like a options menu that says "This mod will do irreversible damage to your world, please backup your worlds before running it" and it would have a ok button you would click that would close the menu and continue to the title screen.

Issue comments

The issue with overriding main GUI is that it will introduce an incompatibility with other mods, so we don't plan to implement this at this point.

Actually adding another point where it opens dialog would require even more core modifications.

We add new text to main GUI in Minecraft Link so if you are fine with text warning on the main screen only, you can check how we did this here: https://github.com/Pylo/MinecraftLink/blob/master/src/main/java/net/mcreator/minecraft/link/gui/ScreenEventHandler.java

Another option is on player joins world trigger and show the warning in the chat.