Condense the Chat research suggestion card

The offer is one card aligned with the message text: a header with its
sources as one link, a two-line brief that expands, suggested additions as
inline rows with icon actions, and a single action row. Refinement failure
becomes a quiet header retry while the brief is usable, dismissed offers
collapse to one line, and the brief editor grows with its text, finishes on
Escape, starts on Command or Control Enter, and leaves you out of its
editors.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>