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/predicate/isEqual.d.mts

@@ -0,0 +1,18 @@
+//#region src/predicate/isEqual.d.ts
+/**
+ * Checks if two values are equal, including support for `Date`, `RegExp`, and deep object comparison.
+ *
+ * @param a - The first value to compare.
+ * @param b - The second value to compare.
+ * @returns `true` if the values are equal, otherwise `false`.
+ *
+ * @example
+ * isEqual(1, 1); // true
+ * isEqual({ a: 1 }, { a: 1 }); // true
+ * isEqual(/abc/g, /abc/g); // true
+ * isEqual(new Date('2020-01-01'), new Date('2020-01-01')); // true
+ * isEqual([1, 2, 3], [1, 2, 3]); // true
+ */
+declare function isEqual(a: any, b: any): boolean;
+//#endregion
+export { isEqual };