feat: Reinitialize frontend with SvelteKit and TypeScript

- Delete old Vite+Svelte frontend
- Initialize new SvelteKit project with TypeScript
- Configure Tailwind CSS v4 + DaisyUI
- Implement JWT authentication with auto-refresh
- Create login page with form validation (Zod)
- Add protected route guards
- Update Docker configuration for single-stage build
- Add E2E tests with Playwright (6/11 passing)
- Fix Svelte 5 reactivity with $state() runes

Known issues:
- 5 E2E tests failing (timing/async issues)
- Token refresh implementation needs debugging
- Validation error display timing

frontend/node_modules/happy-dom/lib/browser/BrowserContext.d.ts

@@ -0,0 +1,43 @@
+import ICookieContainer from '../cookie/ICookieContainer.js';
+import IResponseCache from '../fetch/cache/response/IResponseCache.js';
+import Browser from './Browser.js';
+import BrowserPage from './BrowserPage.js';
+import IBrowserContext from './types/IBrowserContext.js';
+import IPreflightResponseCache from '../fetch/cache/preflight/IPreflightResponseCache.js';
+/**
+ * Browser context.
+ */
+export default class BrowserContext implements IBrowserContext {
+    readonly pages: BrowserPage[];
+    readonly browser: Browser;
+    readonly cookieContainer: ICookieContainer;
+    readonly responseCache: IResponseCache;
+    readonly preflightResponseCache: IPreflightResponseCache;
+    /**
+     * Constructor.
+     *
+     * @param browser
+     */
+    constructor(browser: Browser);
+    /**
+     * Aborts all ongoing operations and destroys the context.
+     */
+    close(): Promise<void>;
+    /**
+     * Returns a promise that is resolved when all resources has been loaded, fetch has completed, and all async tasks such as timers are complete.
+     *
+     * @returns Promise.
+     */
+    waitUntilComplete(): Promise<void>;
+    /**
+     * Aborts all ongoing operations.
+     */
+    abort(): Promise<void>;
+    /**
+     * Creates a new page.
+     *
+     * @returns Page.
+     */
+    newPage(): BrowserPage;
+}
+//# sourceMappingURL=BrowserContext.d.ts.map