Add settings page for managing forecasting API key and URL via UI

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/node_modules/es-toolkit/dist/compat/math/meanBy.d.ts

@@ -0,0 +1,28 @@
+import { ValueIteratee } from "../_internal/ValueIteratee.js";
+
+//#region src/compat/math/meanBy.d.ts
+/**
+ * Calculates the average of an array of numbers when applying
+ * the `iteratee` function to each element.
+ *
+ * If the array is empty, this function returns `NaN`.
+ *
+ * @template T - The type of elements in the array.
+ * @param items An array to calculate the average.
+ * @param iteratee
+ * The criteria used to determine the maximum value.
+ *  - If a **function** is provided, it extracts a numeric value from each element.
+ *  - If a **string** is provided, it is treated as a key to extract values from the objects.
+ *  - If a **[key, value]** pair is provided, it matches elements with the specified key-value pair.
+ *  - If an **object** is provided, it matches elements that contain the specified properties.
+ * @returns The average of all the numbers as determined by the `iteratee` function.
+ *
+ * @example
+ * meanBy([{ a: 1 }, { a: 2 }, { a: 3 }], x => x.a); // Returns: 2
+ * meanBy([], x => x.a); // Returns: NaN
+ * meanBy([[2], [3], [1]], 0); // Returns: 2
+ * meanBy([{ a: 2 }, { a: 3 }, { a: 1 }], 'a'); // Returns: 2
+ */
+declare function meanBy<T>(items: ArrayLike<T> | null | undefined, iteratee?: ValueIteratee<T>): number;
+//#endregion
+export { meanBy };