Make iterators simple functions

addons/observers.luau

@@ -51,8 +51,7 @@ local function observers_new(world, query, callback)
 		world:changed(term, emplaced)
  	end
 
-  	return setmetatable({}, {
+  	return function()
-   		__iter = function()
   		local row = i
   		return function()
      			if row == 0 then
@@ -64,7 +63,6 @@ local function observers_new(world, query, callback)
            	return entity
 		end
     end
-   	})
 end
 
 local function join(world, component)
@@ -152,6 +150,19 @@ local function monitors_new(world, query, callback)
 		world:added(term, emplaced)
 		world:removed(term, removed)
  	end
+
+	return function()
+		local row = i
+		return function()
+			if row == 0 then
+				i = 0
+				table.clear(entities)
+			end
+			local entity = entities[row]
+			row -= 1
+			return entity
+		end
+	end
 end
 
 local function observers_add(world: jecs.World): PatchedWorld