Initial commit: Brachnha Insight project setup

- Next.js 14+ with App Router and TypeScript
- Tailwind CSS and ShadCN UI styling
- Zustand state management
- Dexie.js for IndexedDB (local-first data)
- Auth.js v5 for authentication
- BMAD framework integration

Co-Authored-By: Claude <noreply@anthropic.com>

vitest.setup.ts

@@ -0,0 +1,14 @@
+import { expect, afterEach } from 'vitest';
+import { cleanup } from '@testing-library/react';
+import '@testing-library/jest-dom/vitest'; // Direct side-effect import for Vitest
+import 'fake-indexeddb/auto';
+
+// No need for expect.extend check if we use the side-effect import above,
+// but for safety in older versions:
+import * as matchers from '@testing-library/jest-dom/matchers';
+expect.extend(matchers);
+
+// Cleanup after each test
+afterEach(() => {
+  cleanup();
+});