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-media-element/MediaStream.d.ts

@@ -0,0 +1,60 @@
+import * as PropertySymbol from '../../PropertySymbol.js';
+import EventTarget from '../../event/EventTarget.js';
+import MediaStreamTrackEvent from '../../event/events/MediaStreamTrackEvent.js';
+import MediaStreamTrack from './MediaStreamTrack.js';
+/**
+ * MediaStream.
+ *
+ * @see https://developer.mozilla.org/en-US/docs/Web/API/MediaStream
+ */
+export default class MediaStream extends EventTarget {
+    active: boolean;
+    id: string;
+    onaddtrack: ((event: MediaStreamTrackEvent) => void) | null;
+    onremovetrack: ((event: MediaStreamTrackEvent) => void) | null;
+    [PropertySymbol.tracks]: MediaStreamTrack[];
+    /**
+     * Constructor.
+     *
+     * @param [streamOrTracks] Stream or tracks.
+     */
+    constructor(streamOrTracks?: MediaStream | MediaStreamTrack[]);
+    /**
+     * Adds a track.
+     *
+     * @param track Track.
+     */
+    addTrack(track: MediaStreamTrack): void;
+    /**
+     * Returns a clone.
+     *
+     * @returns Clone.
+     */
+    clone(): MediaStream;
+    /**
+     * Returns audio tracks.
+     *
+     * @returns Audio tracks.
+     */
+    getAudioTracks(): MediaStreamTrack[];
+    /**
+     * Returns track by id.
+     *
+     * @param id Id.
+     * @returns Track.
+     */
+    getTrackById(id: string): MediaStreamTrack | null;
+    /**
+     * Returns video tracks.
+     *
+     * @returns Video tracks.
+     */
+    getVideoTracks(): MediaStreamTrack[];
+    /**
+     * Removes a track.
+     *
+     * @param track Track.
+     */
+    removeTrack(track: MediaStreamTrack): void;
+}
+//# sourceMappingURL=MediaStream.d.ts.map