This directory is served at /assets/... (see main.py: app.add_static_files).

startup.mp3 is missing - I can't generate actual audio, so the splash
screen currently plays silence for a source that doesn't exist (the
<audio> tag will just fail to load, which is harmless - the fade
animation still runs on its own timer, it just won't be accompanied by
sound until you add a real file here).

To enable the startup sound:
  1. Drop a ~2 second .mp3 file at assets/startup.mp3
  2. If it's not close to 2 seconds, adjust _HOLD_SECONDS / _FADE_SECONDS
     in stasis_client/components/splash.py so the fade finishes roughly
     when the clip does.