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/template.d.ts

@@ -0,0 +1,30 @@
+import { escape } from "./escape.js";
+
+//#region src/compat/string/template.d.ts
+declare const templateSettings: {
+  escape: RegExp;
+  evaluate: RegExp;
+  interpolate: RegExp;
+  variable: string;
+  imports: {
+    _: {
+      escape: typeof escape;
+      template: typeof template;
+    };
+  };
+};
+interface TemplateOptions {
+  escape?: RegExp | null | undefined;
+  evaluate?: RegExp | null | undefined;
+  interpolate?: RegExp | null | undefined;
+  variable?: string | undefined;
+  imports?: Record<string, any> | undefined;
+  sourceURL?: string;
+}
+interface TemplateExecutor {
+  (data?: object): string;
+  source: string;
+}
+declare function template(string?: string, options?: TemplateOptions): TemplateExecutor;
+//#endregion
+export { template, templateSettings };