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/combinations.d.ts

@@ -0,0 +1,35 @@
+//#region src/array/combinations.d.ts
+/**
+ * Returns all `r`-length combinations of elements from the input array.
+ *
+ * Combinations are emitted in lexicographic order based on the position of elements in the input array.
+ * Elements are treated as unique by position, not by value, so duplicates in the input may produce
+ * combinations that look identical.
+ *
+ * The number of combinations is `n! / r! / (n - r)!` when `0 <= r <= n`, and zero when `r > n`.
+ *
+ * @template T
+ * @param arr - The input array.
+ * @param r - The length of each combination. Must be a non-negative integer.
+ * @returns An array of `r`-length combinations.
+ * @throws {Error} If `r` is not a non-negative integer.
+ *
+ * @example
+ * combinations(['A', 'B', 'C', 'D'], 2);
+ * // => [['A','B'], ['A','C'], ['A','D'], ['B','C'], ['B','D'], ['C','D']]
+ *
+ * @example
+ * combinations([1, 2, 3, 4], 3);
+ * // => [[1,2,3], [1,2,4], [1,3,4], [2,3,4]]
+ *
+ * @example
+ * combinations([1, 2, 3], 0);
+ * // => [[]]
+ *
+ * @example
+ * combinations([1, 2], 5);
+ * // => []
+ */
+declare function combinations<T>(arr: readonly T[], r: number): T[][];
+//#endregion
+export { combinations };