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/compat/string/capitalize.d.mts

@@ -0,0 +1,15 @@
+//#region src/compat/string/capitalize.d.ts
+/**
+ * Converts the first character of string to upper case and the remaining to lower case.
+ *
+ * @param string - The string to capitalize.
+ * @returns The capitalized string.
+ *
+ * @example
+ * const convertedStr1 = capitalize('fred') // returns 'Fred'
+ * const convertedStr2 = capitalize('FRED') // returns 'Fred'
+ * const convertedStr3 = capitalize('') // returns ''
+ */
+declare function capitalize<T extends string>(str?: T): string extends T ? string : Capitalize<Lowercase<T>>;
+//#endregion
+export { capitalize };