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/intersectionBy.d.ts

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+//#region src/array/intersectionBy.d.ts
+/**
+ * Returns the intersection of two arrays based on a mapping function.
+ *
+ * This function takes two arrays and a mapping function. It returns a new array containing
+ * the elements from the first array that, when mapped using the provided function, have matching
+ * mapped elements in the second array. It effectively filters out any elements from the first array
+ * that do not have corresponding mapped values in the second array.
+ *
+ * @template T - The type of elements in the first array.
+ * @template U - The type of elements in the second array.
+ * @param firstArr - The first array to compare.
+ * @param secondArr - The second array to compare.
+ * @param mapper - A function to map the elements of both arrays for comparison.
+ * @returns A new array containing the elements from the first array that have corresponding mapped values in the second array.
+ *
+ * @example
+ * const array1 = [{ id: 1 }, { id: 2 }, { id: 3 }];
+ * const array2 = [{ id: 2 }, { id: 4 }];
+ * const mapper = item => item.id;
+ * const result = intersectionBy(array1, array2, mapper);
+ * // result will be [{ id: 2 }] since only this element has a matching id in both arrays.
+ *
+ * @example
+ * const array1 = [
+ *   { id: 1, name: 'jane' },
+ *   { id: 2, name: 'amy' },
+ *   { id: 3, name: 'michael' },
+ * ];
+ * const array2 = [2, 4];
+ * const mapper = item => (typeof item === 'object' ? item.id : item);
+ * const result = intersectionBy(array1, array2, mapper);
+ * // result will be [{ id: 2, name: 'amy' }] since only this element has a matching id that is equal to seconds array's element.
+ */
+declare function intersectionBy<T, U>(firstArr: readonly T[], secondArr: readonly U[], mapper: (item: T | U) => unknown): T[];
+//#endregion
+export { intersectionBy };