⬆️(frontend) upgrade posthog-js from 1.395.0 to 1.404.1

Minor version upgrade with bug fixes and internal improvements. No
breaking changes, API deprecations or required actions on our side.

Highlights:

* Better handling of `sendBeacon` quota rejections so events are no
  longer silently dropped.
* Improved error catching for synchronous throws from a
  monkey-patched `window.fetch`.
* Source map improvements for easier debugging.

src/frontend/package.json

@@ -36,7 +36,7 @@
     "i18next-parser": "9.4.0",
     "i18next-resources-to-backend": "1.2.1",
     "livekit-client": "2.20.0",
-    "posthog-js": "1.395.0",
+    "posthog-js": "1.404.1",
     "react": "18.3.1",
     "react-aria": "3.50.0",
     "react-aria-components": "1.19.0",