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/fp/array/union.js

@@ -0,0 +1,25 @@
+const require_union = require("../../array/union.js");
+//#region src/fp/array/union.ts
+/**
+* Creates a function that returns unique values from the piped array and secondArray.
+*
+* Values keep their first occurrence order, matching the main {@link union} behavior.
+* Use the returned function with {@link pipe}.
+*
+* @template T - The type of elements in the arrays.
+* @param secondArray - Values to include after the piped array.
+* @returns A function that maps a readonly array to its union with secondArray.
+*
+* @example
+* import { pipe, union } from 'es-toolkit/fp';
+*
+* pipe([1, 2], union([2, 3]));
+* // => [1, 2, 3]
+*/
+function union(secondArray) {
+	return function(array) {
+		return require_union.union(array, secondArray);
+	};
+}
+//#endregion
+exports.union = union;