- Added new `Dispatcher` interface. A dispatcher can represent a Player, Entity, Block, or even the Server.
- Holders (e.g. Enchantment Levels, Talismans, EcoItems) are no longer held by Players, but by Dispatchers
- Chains / Effects are now triggered by Dispatchers
- Conditions are now checked against Dispatchers
- Triggers are now triggered by Dispatchers

For Developers:
- Deprecated most core API methods and replaced them with new Dispatcher-based methods: e.g. `registerHolderProvider` has been replaced with `registerSpecificHolderProvider<T>` and `registerGenericHolderProvider`
- `Effect#onEnable` and `Effect#onDisable` have had the player versions deprecated and replaced with new versions that take Dispatchers. Update your effects!
- `Condition#isMet` has had the player version deprecated and replaced with a new version that takes a Dispatcher
- All methods like `Player#holders`, `Player#updateHolders`, etc. have been deprecated and replaced with `Dispatcher<*>#holders` etc.

To convert between an `Entity` and a `Dispatcher`, just do `Entity#toDispatcher` - the core flow and most method names have remained the same.

Your existing Effects, Conditions, etc. will still work, however you should update them ASAP as the old methods will eventually be removed!