Refactor /narrate into standalone plugin (with API)

[vorburger]

Using https://docs.spongepowered.org/stable/en/plugin/manager.html?

Or can any plugin just @Inject something from another 🔌 plugin?! https://docs.adventure.kyori.net/platform/spongeapi.html (for #326) makes it look like so. Or is that the"Services" from Sponge 7 which are going away with Sponge 8?

It requires declaring the dependency in JSON , for correctly ordering plugin initialisation, as explained here.

Add it to https://ore.spongepowered.org