separate bonemealable plants from terrain spawnable plants

[xkforce]

Some plants might be intended to spawn in the terrain but not be bonemealable and vice versa. eg. truffles IRL cant be farmed but can be scavenged. In minecraft the equivalent of this would be making an arbitrary block able to spawn in the terrain but not allow it to be bonemealed. Alternatively IRL eutrophication of large bodies of water like lakes and rivers can be overtaken by algae if fertilizer runoff reaches a critical level. In minecraft the equivalent of this would be to disable spawning of a given block in the terrain but allow it to be a product of bonemealing. A negative environmental consequence to the player bonemealing everything.