Between sending the report prompt and the writer actually starting to
generate, the spinner was already dropped, so the terminal went blank
for however long that gap was. Thread the spinner into
write_text_stream instead and stop it right as the first chunk
arrives, covering the wait with the same "Writing report..." line
rather than clearing it early.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
