feat: integrate Mock Service Worker (MSW) for API mocking and testing

Currently just used for demo page

- Added MSW as a dependency in package.json.
- Configured MSW in the demo HTML to start the worker and handle API requests.
- Created mockServiceWorker.js to manage service worker lifecycle and request handling.
- Implemented browser.ts to set up the MSW worker with defined request handlers.
- Developed handlers.ts to simulate API responses and manage application state for testing.
diff --git a/webui/src/web-components/demo/mocks/browser.ts b/webui/src/web-components/demo/mocks/browser.ts
new file mode 100644
index 0000000..bcd82e4
--- /dev/null
+++ b/webui/src/web-components/demo/mocks/browser.ts
@@ -0,0 +1,4 @@
+import { setupWorker } from "msw/browser";
+import { handlers } from "./handlers";
+
+export const worker = setupWorker(...handlers);