The mobile feed stopped shimmering the running tool row once a call
completed, and never showed the "Thinking" live activity row web has.

Mirror web's live-row rules: the trailing run keeps shining after its
latest call succeeds, only a failed, declined, or stopped call hands
the slot to "Thinking", and a working turn with no live tool row shows
"Thinking" on its own.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>