New component that will replace the task-lane SuggestedFix card. Docks above the chat composer with a 320ms slide-up animation. This commit implements only the Proposed state (Tasks 8 & 9 fill Verifying, Partial, AI-confirming, Nudge, Collapsed). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>