- Add onBookmark/isBookmarked props to ChatMessageActions
- Render ChatMessageBookmark as last action for user and assistant messages
- Add onBookmark/isBookmarked props to ChatMessage, thread to ChatMessageActions
- System messages do not receive bookmark actions
- Add id, isAnyStreaming, onEdit, onRetry props to ChatMessageProps
- User messages show edit Pencil on hover via ChatMessageActions
- Edit pencil opens inline textarea with Save/Discard buttons
- Save edit calls onEdit(id, newContent), disabled when textarea empty
- Discard edit reverts to read-only bubble
- Assistant messages show retry RefreshCw via ChatMessageActions
- All edit/retry actions disabled when isAnyStreaming is true
- Update test stubs to reflect new prop surface
- Create ChatMessageIdentityBar with agent icon, name, timestamp, and streaming dot
- Create ChatStreamingCursor with animate-cursor-blink and aria-hidden
- Extend ChatMessage with agentName, agentIcon, agentRole, timestamp, isStreaming props
- Wrap assistant messages in group div for hover actions (Plan 03)
- Create agent-role-colors.ts with 11 distinct role colors (light + dark variants)
- Create ChatMarkdownMessage prerequisite from phase-21 base
- All 4 ChatMessageIdentityBar tests pass