Restore codebase deleted by bad auto-commit e4227cf

Commit e4227cf (a story creation auto-commit) erroneously deleted 175
files from master's tree, likely due to a race condition between
concurrent git operations. This commit re-adds all files from the
working directory.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/setupTests.ts

@@ -0,0 +1,20 @@
+import "@testing-library/jest-dom";
+import { beforeEach, vi } from "vitest";
+
+// Provide a default fetch mock so components that call API endpoints on mount
+// don't throw URL-parse errors in the jsdom test environment.  Tests that need
+// specific responses should mock the relevant `api.*` method as usual.
+beforeEach(() => {
+	vi.stubGlobal(
+		"fetch",
+		vi.fn((input: string | URL | Request) => {
+			const url = typeof input === "string" ? input : input.toString();
+			// Endpoints that return arrays need [] not {} to avoid "not iterable" errors.
+			const arrayEndpoints = ["/agents", "/agents/config"];
+			const body = arrayEndpoints.some((ep) => url.endsWith(ep))
+				? JSON.stringify([])
+				: JSON.stringify({});
+			return Promise.resolve(new Response(body, { status: 200 }));
+		}),
+	);
+});