Fix Lua memory leaks related to dangling handles

src/main/kotlin/ru/dbotthepony/kstarbound/lua/CommonHandleRegistry.kt

@@ -1,6 +1,10 @@
 package ru.dbotthepony.kstarbound.lua
 
 data class CommonHandleRegistry(
-	val future: LuaHandle,
-	val pathFinder: LuaHandle,
-)
+	val future: LuaHandle = LuaHandle.Nil,
+	val pathFinder: LuaHandle = LuaHandle.Nil,
+) {
+	companion object {
+		val EMPTY = CommonHandleRegistry()
+	}
+}

src/main/kotlin/ru/dbotthepony/kstarbound/lua/Conversions.kt

@@ -176,10 +176,10 @@ fun LuaThread.getVector2iOrAABB(stackIndex: Int = -1): Either<Vector2i, AABB>? {
 
 fun LuaThread.ArgStack.nextVector2iOrAABB(position: Int = this.position++): Either<Vector2i, AABB> {
 	if (position !in 1 ..this.top)
-		throw IllegalArgumentException("bad argument #$position: Vector2d expected, got nil")
+		throw IllegalArgumentException("bad argument #$position: Vector2i expected, got nil")
 
 	return lua.getVector2iOrAABB(position)
-		?: throw IllegalArgumentException("bad argument #$position: Vector2d or AABB expected, got ${lua.typeAt(position)}")
+		?: throw IllegalArgumentException("bad argument #$position: Vector2i or AABB expected, got ${lua.typeAt(position)}")
 }
 
 fun LuaThread.ArgStack.nextOptionalVector2iOrAABB(position: Int = this.position++): Either<Vector2i, AABB>? {

src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaHandle.kt

@@ -7,6 +7,7 @@ import ru.dbotthepony.kstarbound.Starbound
 import ru.dbotthepony.kstarbound.json.InternedJsonElementAdapter
 import java.io.Closeable
 import java.lang.ref.Cleaner.Cleanable
+import java.lang.ref.WeakReference
 
 interface LuaHandle : Closeable {
 	fun push(into: LuaThread)
@@ -127,12 +128,12 @@ interface LuaHandle : Closeable {
 		}
 
 		init {
-			val parent = parent
+			val parent = WeakReference(parent)
 			val handle = handle
 			val key = key
 
 			cleanable = Starbound.CLEANER.register(this) {
-				parent.freeHandle(handle, key)
+				parent.get()?.freeHandle(handle, key)
 			}
 
 		}

src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaSharedState.kt

@@ -45,6 +45,9 @@ class LuaSharedState(val handlesThread: LuaThread, private val cleanable: Cleana
 		isValid = false
 		namedHandles.clear()
 		cleanable.clean()
+		errorToStringFunction = LuaHandle.Nil
+		errorTrapFunction = LuaHandle.Nil
+		commonHandles = CommonHandleRegistry.EMPTY
 	}
 
 	fun initializeHandles(mainThread: LuaThread) {

src/main/kotlin/ru/dbotthepony/kstarbound/world/entities/MonsterEntity.kt

@@ -406,10 +406,10 @@ class MonsterEntity(val variant: MonsterVariant, level: Double? = null) : ActorE
 				}
 			} else {
 				try {
-					luaUpdate.update(delta) {
+					/*luaUpdate.update(delta) {
 						luaMovement.clearControlsIfNeeded()
 						forceRegions.clear()
-					}
+					}*/
 				} catch (err: Exception) {
 					LOGGER.error("Exception while ticking $this", err)
 				}