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/limitAsync.js

@@ -0,0 +1,46 @@
+const require_semaphore = require("../promise/semaphore.js");
+//#region src/array/limitAsync.ts
+/**
+* Wraps an async function to limit the number of concurrent executions.
+*
+* This function creates a wrapper around an async callback that ensures at most
+* `concurrency` number of executions can run simultaneously. Additional calls will
+* wait until a slot becomes available.
+*
+* @template F - The type of the async function to wrap.
+* @param callback The async function to wrap with concurrency control.
+* @param concurrency Maximum number of concurrent executions allowed.
+* @returns A wrapped version of the callback with concurrency limiting.
+* @example
+* const limitedFetch = limitAsync(async (url) => {
+*   return await fetch(url);
+* }, 3);
+*
+* // Only 3 fetches will run concurrently
+* const urls = ['url1', 'url2', 'url3', 'url4', 'url5'];
+* await Promise.all(urls.map(url => limitedFetch(url)));
+*
+* @example
+* const processItem = async (item) => {
+*   // Expensive async operation
+*   return await heavyComputation(item);
+* };
+*
+* const limitedProcess = limitAsync(processItem, 2);
+* const items = [1, 2, 3, 4, 5];
+* // At most 2 items will be processed concurrently
+* await Promise.all(items.map(item => limitedProcess(item)));
+*/
+function limitAsync(callback, concurrency) {
+	const semaphore = new require_semaphore.Semaphore(concurrency);
+	return async function(...args) {
+		try {
+			await semaphore.acquire();
+			return await callback.apply(this, args);
+		} finally {
+			semaphore.release();
+		}
+	};
+}
+//#endregion
+exports.limitAsync = limitAsync;