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/zod/src/v3/tests/mocker.test.ts

@@ -0,0 +1,19 @@
+// @ts-ignore TS6133
+import { test } from "vitest";
+
+import { Mocker } from "./Mocker.js";
+
+test("mocker", () => {
+  const mocker = new Mocker();
+  mocker.string;
+  mocker.number;
+  mocker.boolean;
+  mocker.null;
+  mocker.undefined;
+  mocker.stringOptional;
+  mocker.stringNullable;
+  mocker.numberOptional;
+  mocker.numberNullable;
+  mocker.booleanOptional;
+  mocker.booleanNullable;
+});