Implement default PlayerDisplayNameProvider API

[TechnicJelle]

Implemented a default for the API added in BlueMap-Minecraft/BlueMapAPI#9

I'm not all too happy about it all yet, especially the locations of some things and what I had to pass into other places.
Also, the default implementation currently kind of sucks.

I'd be happy to get feedback on this!

Screenshots of this working

Addon plugin code

package com.TechnicJelle.blueMapCustomPlayerNames;

import de.bluecolored.bluemap.api.BlueMapAPI;
import net.kyori.adventure.text.Component;
import net.kyori.adventure.text.TextComponent;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;

import java.util.function.Consumer;

public final class BlueMapCustomPlayerNames extends JavaPlugin {

    @Override
    public void onEnable() {
        BlueMapAPI.onEnable(bluemapOnEnable);
    }

    Consumer<BlueMapAPI> bluemapOnEnable = (BlueMapAPI api) -> {
        api.getPlugin().setPlayerNameProvider(playerUUID -> {
            Player player = getServer().getPlayer(playerUUID);
            if (player == null) return playerUUID.toString();

            Component displayName = player.displayName();
            if (displayName instanceof TextComponent textComponent)
                return "<span style=\"color: blue;\">" + textComponent.content() + "</span>";

            return playerUUID.toString();
        });
    };
}

[TBlueF]

I would be fine with changing the Server#getOnlinePLayer() method into a Map<UUID, Player> .. this would then also need to be implemented in all implementations though ofc..

[TBlueF]

I already don't like passing the PluginConfig here, now also passing the Plugin screams that this needs to be refactored somehow that this is not needed.
For now, passing the PlayerDisplayNameProvider directly would be the most passable i think ..