Add BreakEvent Check to harvesting

[Caltinor]

Hello,

This is a request to add a BreakEvent check in CropHarvest.java.

The purpose would be to allow other mods to capture harvest events from right clicks in a way that is cancellable and or trackable. Use cases would include protection mods that might want to prevent harvesting under certain conditions, and/or stat tracking mods that want to properly deliver awards to players for harvest actions.

I am willing to build a PR for this, if that is your preference.