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/array/intersection.mjs

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+//#region src/array/intersection.ts
+/**
+* Returns the intersection of two arrays.
+*
+* This function takes two arrays and returns a new array containing the elements that are
+* present in both arrays. It effectively filters out any elements from the first array that
+* are not found in the second array.
+*
+* @template T - The type of elements in the array.
+* @param firstArr - The first array to compare.
+* @param secondArr - The second array to compare.
+* @returns A new array containing the elements that are present in both arrays.
+*
+* @example
+* const array1 = [1, 2, 3, 4, 5];
+* const array2 = [3, 4, 5, 6, 7];
+* const result = intersection(array1, array2);
+* // result will be [3, 4, 5] since these elements are in both arrays.
+*/
+function intersection(firstArr, secondArr) {
+	const secondSet = new Set(secondArr);
+	return firstArr.filter((item) => secondSet.has(item));
+}
+//#endregion
+export { intersection };