public static @NotNull UserCapabilityImpl get(@NotNull Player player) {
        return (UserCapabilityImpl) getCapability(player).orElseThrow(() -> new IllegalStateException("Capability missing for " + player.getUUID()));
    }
Gets a {@link UserCapability} for a given {@link ServerPlayer}.

@param player the player
@return the capability
forge/src/main/java/me/lucko/luckperms/forge/capabilities/UserCapabilityImpl.java