Added polyfill for Object.groupBy (#730)

src/hooks.ts

@@ -2,3 +2,18 @@ import "./dayjs-plugins";
 
 import { i18n } from "$lib/utils/i18n";
 export const reroute = i18n.reroute();
+
+// Polyfill Object.groupBy
+if (typeof Object.groupBy === typeof undefined) {
+  Object.groupBy = <K extends PropertyKey, T>(
+    items: Iterable<T>,
+    keySelector: (item: T, index: number) => K,
+  ): Partial<Record<K, T[]>> => {
+    return Array.from(items).reduce((acc: Partial<Record<K, T[]>>, ...args) => {
+      const key = keySelector(args[0], args[1]);
+      acc[key] ??= [];
+      acc[key].push(args[0]);
+      return acc;
+    }, {});
+  };
+}