feat: use new ActiveEffect transferral system

Closes #68

src/migration/009.js

@@ -0,0 +1,40 @@
+// SPDX-FileCopyrightText: 2023 Johannes Loher
+//
+// SPDX-License-Identifier: MIT
+
+import {
+    getSceneMigrator,
+    migrateCollection,
+    migrateCompendiums,
+    getCompendiumMigrator,
+    getActorMigrator,
+} from "./migrationHelpers.js";
+
+/** @type {import("./migration.js").Migration["migrate"]} */
+async function migrate() {
+    await migrateCollection(game.actors, migrateActor);
+    await migrateCollection(game.scenes, migrateScene);
+    await migrateCompendiums(migrateCompendium);
+}
+
+const itemIdRegex = /Item\.([a-zA-Z0-9]+)/;
+
+/** @type {import('./migrationHelpers.js').Migrator<ActiveEffect>} */
+async function migrateActiveEffect(activeEffect) {
+    if (activeEffect.parent instanceof Actor) {
+        const itemId = activeEffect.origin?.match(itemIdRegex)?.[1];
+        if (activeEffect.parent.items.has(itemId)) {
+            await activeEffect.delete();
+        }
+    }
+}
+
+const migrateActor = getActorMigrator(undefined, migrateActiveEffect);
+const migrateScene = getSceneMigrator(migrateActor);
+const migrateCompendium = getCompendiumMigrator({ migrateActor, migrateScene });
+
+/** @type {import("./migration.js").Migration} */
+export const migration = {
+    migrate,
+    migrateCompendium,
+};

src/migration/migration.js

@@ -13,6 +13,7 @@ import { migration as migration005 } from "./005.js";
 import { migration as migration006 } from "./006.js";
 import { migration as migration007 } from "./007.js";
 import { migration as migration008 } from "./008.js";
+import { migration as migration009 } from "./009.js";
 
 /**
  * Perform migrations.
@@ -176,6 +177,7 @@ const migrations = [
     migration006,
     migration007,
     migration008,
+    migration009,
 ];
 
 /**