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/nodes/html-template-element/HTMLTemplateElement.d.ts

@@ -0,0 +1,72 @@
+import HTMLElement from '../html-element/HTMLElement.js';
+import * as PropertySymbol from '../../PropertySymbol.js';
+import DocumentFragment from '../document-fragment/DocumentFragment.js';
+import Node from '../node/Node.js';
+import ShadowRoot from '../shadow-root/ShadowRoot.js';
+/**
+ * HTML Template Element.
+ *
+ * Reference:
+ * https://developer.mozilla.org/en-US/docs/Web/API/HTMLTemplateElement.
+ */
+export default class HTMLTemplateElement extends HTMLElement {
+    cloneNode: (deep?: boolean) => HTMLTemplateElement;
+    [PropertySymbol.content]: DocumentFragment;
+    /**
+     * Returns content.
+     *
+     * @returns Content.
+     */
+    get content(): DocumentFragment;
+    /**
+     * @override
+     */
+    get innerHTML(): string;
+    /**
+     * @override
+     */
+    set innerHTML(html: string);
+    /**
+     * @override
+     */
+    get firstChild(): Node;
+    /**
+     * @override
+     */
+    get lastChild(): Node;
+    /**
+     * @deprecated
+     * @override
+     */
+    getInnerHTML(_options?: {
+        includeShadowRoots?: boolean;
+    }): string;
+    /**
+     * @override
+     */
+    getHTML(_options?: {
+        serializableShadowRoots?: boolean;
+        shadowRoots?: ShadowRoot[];
+    }): string;
+    /**
+     * @override
+     */
+    [PropertySymbol.appendChild](node: Node, disableValidations?: boolean): Node;
+    /**
+     * @override
+     */
+    [PropertySymbol.removeChild](node: Node): Node;
+    /**
+     * @override
+     */
+    [PropertySymbol.insertBefore](newNode: Node, referenceNode: Node, disableValidations?: boolean): Node;
+    /**
+     * @override
+     */
+    [PropertySymbol.replaceChild](newChild: Node, oldChild: Node): Node;
+    /**
+     * @override
+     */
+    [PropertySymbol.cloneNode](deep?: boolean): HTMLTemplateElement;
+}
+//# sourceMappingURL=HTMLTemplateElement.d.ts.map