Feature/register helper

[mineLdiver]

Added helper methods for registering new entries to registries.

Examples:

1. Singular registration

@EventListener
void registerBlocks(BlockRegistryEvent event) {
    event.register(Namespace.MINECRAFT.id("stone"), Block.STONE);
}

2. Singular registration with explicit raw ID

@EventListener
void registerBlocks(BlockRegistryEvent event) {
    event.register(Block.STONE.id, Namespace.MINECRAFT.id("stone"), Block.STONE);
}

3. Bulk registration

@EventListener
void registerBlocks(BlockRegistryEvent event) {
    event.register()
        .accept(Namespace.MINECRAFT.id("stone"), Block.STONE)
        .accept(Namespace.MINECRAFT.id("dirt"), Block.DIRT)
        .accept(Namespace.MINECRAFT.id("obsidian"), Block.OBSIDIAN);
}

4. Bulk registration with common namespace

@EventListener
void registerBlocks(BlockRegistryEvent event) {
    event.register(Namespace.MINECRAFT)
        .accept("stone", Block.STONE)
        .accept("dirt", Block.DIRT)
        .accept("obsidian", Block.OBSIDIAN);
}

5. Bulk registration with common namespace and explicit raw ID

@EventListener
void registerBlocks(BlockRegistryEvent event) {
    event.register(block -> block.id, Namespace.MINECRAFT)
        .accept("stone", Block.STONE)
        .accept("dirt", Block.DIRT)
        .accept("obsidian", Block.OBSIDIAN);
}

6. Bulk registration outside of an event

Registry.register(BlockRegistry.INSTANCE)
    .accept(Namespace.MINECRAFT.id("stone"), Block.STONE)
    .accept(Namespace.MINECRAFT.id("dirt"), Block.DIRT)
    .accept(Namespace.MINECRAFT.id("obsidian"), Block.OBSIDIAN);

7. Bulk registration outside of an event with common namespace

Registry.register(BlockRegistry.INSTANCE, Namespace.MINECRAFT)
    .accept("stone", Block.STONE)
    .accept("dirt", Block.DIRT)
    .accept("obsidian", Block.OBSIDIAN);

8. Bulk registration outside of an event with common namespace and explicit raw ID

Registry.register(BlockRegistry.INSTANCE, block -> block.id, Namespace.MINECRAFT)
    .accept("stone", Block.STONE)
    .accept("dirt", Block.DIRT)
    .accept("obsidian", Block.OBSIDIAN);

The event methods are only available in a subclass of RegistryEvent, specifically RegistryEvent.EntryTypeBound, because the RegistryEvent doesn't define the registry's entry generic type (so Block for BlockRegistry), making it impossible to implement type-safe helper methods. Defining the generic type in a subclass allows to introduce these helper methods in a backwards-compatible way. All StationAPI registry events were updated to extend RegistryEvent.EntryTypeBound, and all usages of Registry#register were changed to the helper methods where applicable.

[calmilamsy]

Otherwise, this is a HUGE QoL improvement.

[calmilamsy]

Might be an idea to add a helper method inside Registry that just requires the registry instance and returns this for you.

[mineLdiver]

Good idea, didn't think of that.