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/array/concat.js

@@ -0,0 +1,34 @@
+const require_flatten = require("../../array/flatten.js");
+//#region src/compat/array/concat.ts
+/**
+* Concatenates multiple arrays and values into a single array.
+*
+* @template T The type of elements in the array.
+* @param values - The values and/or arrays to concatenate.
+* @returns A new array containing all the input values.
+*
+* @example
+* // Concatenate individual values
+* concat(1, 2, 3);
+* // returns [1, 2, 3]
+*
+* @example
+* // Concatenate arrays of values
+* concat([1, 2], [3, 4]);
+* // returns [1, 2, 3, 4]
+*
+* @example
+* // Concatenate a mix of individual values and arrays
+* concat(1, [2, 3], 4);
+* // returns [1, 2, 3, 4]
+*
+* @example
+* // Concatenate nested arrays
+* concat([1, [2, 3]], 4);
+* // returns [1, [2, 3], 4]
+*/
+function concat(...values) {
+	return require_flatten.flatten(values);
+}
+//#endregion
+exports.concat = concat;