界面与通知 · ui_feedback create subtle

Create a subtle AI assistant waiting / thinking sound effect. The sound should be soft, warm, calm, and non-intrusive. It should feel like a gentle pulsing or breathing tone, with very light low-frequency “dum… dum…” movement. It should quietly indicate that the assistant is processing, searching, or thinking, without distracting the user or competing with speech. Style requirements: - very gentle and minimal - low