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/promise/timeout.mjs

@@ -0,0 +1,49 @@
+import { TimeoutError } from "../error/TimeoutError.mjs";
+//#region src/promise/timeout.ts
+/**
+* Returns a promise that rejects with a `TimeoutError` after a specified delay.
+*
+* You can pass an `AbortSignal` to cancel the timeout. Unlike most `AbortSignal`-aware
+* APIs, aborting does **not** reject the promise. A `timeout` only exists to lose a
+* `Promise.race`, so cancelling it leaves the promise pending forever, allowing the
+* operation it guards to settle on its own. The underlying timer and abort listener
+* are cleared on abort, so nothing is leaked.
+*
+* @param ms - The delay duration in milliseconds.
+* @param options - The options object.
+* @param options.signal - An optional AbortSignal to cancel the timeout. When aborted, the returned promise never settles.
+* @returns A promise that rejects with a `TimeoutError` after the specified delay, or never settles if aborted.
+* @throws {TimeoutError} Throws a `TimeoutError` after the specified delay.
+*
+* @example
+* try {
+*   await timeout(1000); // Timeout exception after 1 second
+* } catch (error) {
+*   console.error(error); // Will log 'The operation was timed out'
+* }
+*
+* @example
+* // Cancelling the timeout lifts the time limit instead of throwing.
+* const controller = new AbortController();
+* setTimeout(() => controller.abort(), 50);
+*
+* const result = await Promise.race([
+*   doWork(),
+*   timeout(1000, { signal: controller.signal }), // never rejects once aborted
+* ]);
+*/
+function timeout(ms, { signal } = {}) {
+	return new Promise((_resolve, reject) => {
+		const abortHandler = () => {
+			clearTimeout(timeoutId);
+		};
+		if (signal?.aborted) return;
+		const timeoutId = setTimeout(() => {
+			signal?.removeEventListener("abort", abortHandler);
+			reject(new TimeoutError());
+		}, ms);
+		signal?.addEventListener("abort", abortHandler, { once: true });
+	});
+}
+//#endregion
+export { timeout };