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/function/spread.d.ts

@@ -0,0 +1,20 @@
+//#region src/function/spread.d.ts
+/**
+ * Creates a new function that spreads elements of an array argument into individual arguments
+ * for the original function.
+ *
+ * @template F - A function type with any number of parameters and any return type.
+ * @param func - The function to be transformed. It can be any function with any number of arguments.
+ * @returns A new function that takes an array of arguments and returns the result of calling the original function with those arguments.
+ *
+ * @example
+ * function add(a, b) {
+ *   return a + b;
+ * }
+ *
+ * const spreadAdd = spread(add);
+ * console.log(spreadAdd([1, 2])); // Output: 3
+ */
+declare function spread<F extends (...args: any[]) => any>(func: F): (argsArr: Parameters<F>) => ReturnType<F>;
+//#endregion
+export { spread };