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/util/attempt.d.mts

@@ -0,0 +1,43 @@
+//#region src/util/attempt.d.ts
+/**
+ * Attempt to execute a function and return the result or error.
+ * Returns a tuple where:
+ * - On success: [null, Result] - First element is null, second is the result
+ * - On error: [Error, null] - First element is the caught error, second is null
+ *
+ * @template {unknown} T - The type of the result of the function.
+ * @template {unknown} E - The type of the error that can be thrown by the function.
+ * @param func - The function to execute.
+ * @returns A tuple containing either [null, result] or [error, null].
+ *
+ * @example
+ * // Successful execution
+ * const [error, result] = attempt(() => 42);
+ * // [null, 42]
+ *
+ * // Failed execution
+ * const [error, result] = attempt(() => {
+ *   throw new Error('Something went wrong');
+ * });
+ * // [Error, null]
+ *
+ * // With type parameter
+ * const [error, names] = attempt<string[]>(() => ['Alice', 'Bob']);
+ * // [null, ['Alice', 'Bob']]
+ *
+ * @note
+ * Important: This function is not suitable for async functions (functions that return a `Promise`).
+ * When passing an async function, it will return `[null, Promise<Result>]`, but won't catch any
+ * errors if the Promise is rejected later.
+ *
+ * For handling async functions, use the `attemptAsync` function instead:
+ * ```
+ * const [error, data] = await attemptAsync(async () => {
+ *   const response = await fetch('https://api.example.com/data');
+ *   return response.json();
+ * });
+ * ```
+ */
+declare function attempt<T, E>(func: () => T): [null, T] | [E, null];
+//#endregion
+export { attempt };