feat: Add tool/harvestability indicator

src/main/kotlin/util/MC.kt

@@ -99,7 +99,7 @@ object MC {
 	inline val soundManager get() = instance.soundManager
 	inline val player: ClientPlayerEntity? get() = TestUtil.unlessTesting { instance.player }
 	inline val camera: Entity? get() = instance.cameraEntity
-	inline val stackInHand: ItemStack? get() = player?.inventory?.mainHandStack
+	inline val stackInHand: ItemStack get() = player?.inventory?.mainHandStack ?: ItemStack.EMPTY
 	inline val guiAtlasManager get() = instance.guiAtlasManager
 	inline val world: ClientWorld? get() = TestUtil.unlessTesting { instance.world }
 	inline val playerName: String? get() = player?.name?.unformattedString

src/main/kotlin/util/SkyblockId.kt

@@ -34,7 +34,7 @@ import moe.nea.firmament.util.json.DashlessUUIDSerializer
  */
 @JvmInline
 @Serializable
-value class SkyblockId(val neuItem: String) {
+value class SkyblockId(val neuItem: String) : Comparable<SkyblockId> {
 	val identifier
 		get() = Identifier.of("skyblockitem",
 		                      neuItem.lowercase().replace(";", "__")
@@ -48,6 +48,10 @@ value class SkyblockId(val neuItem: String) {
 		return neuItem
 	}
 
+	override fun compareTo(other: SkyblockId): Int {
+		return neuItem.compareTo(other.neuItem)
+	}
+
 	/**
 	 * A bazaar stock item id, as returned by the HyPixel bazaar api endpoint.
 	 * These are not equivalent to the in-game ids, or the NEU repo ids, and in fact, do not refer to items, but instead