Desktop: option to suppress the clipboard-change warning toast

The desktop app shows a toast when pasting after something wrote to the clipboard during a Claude turn: "Your app copied to the clipboard during Claude's interaction. If you didn't expect that, check it before pasting."

The warning itself is a good safety feature, but for workflows that intentionally write to the clipboard mid-turn (e.g. automation that stages content for pasting), it fires on every paste and becomes noise. There's currently no way to acknowledge or suppress it.

Request: a "don't warn again" affordance — either a per-session dismissal, a settings toggle, or ideally an allow-once flow that distinguishes expected clipboard writes from unexpected ones.