Actually implement mod code into server

server/game/player.ts

@@ -1,16 +1,18 @@
 import { Container, Cursor, ItemData, ItemStack } from "$/common/inventory.ts";
 import { PlayerInfo, ScreenLayout } from "$/common/protocol.ts";
-import { Tile } from "./world.ts";
 
 export const INVENTORY_SIZE = 9 * 4;
 export const CRAFTING_SIZE = 10;
 
-// a screen the server opened for this player, showing a tile's container
+// a container screen a mod opened for this player, see ctx.ui.open_container
 export interface OpenScreen {
-	tile: Tile;
 	container: Container;
 	layout: ScreenLayout;
-	properties(): Record<string, number>;
+	// what the bars show, synced when they change
+	properties: Record<string, number>;
+	// what can go into each slot, checked when the player clicks
+	filters: Map<number, (item: ItemStack) => boolean>;
+	on_close: (() => void)[];
 }
 
 // what's saved about a player between sessions, by name