Function SessionEmptyState

SessionEmptyState(__namedParameters: SessionEmptyStateProps): Element
SessionEmptyState - Shared empty state component for session-based features

When no files exist, displays an icon, message, and optional create button above a bare file list. When files exist, collapses the empty state and shows a toolbar with Create + Delete + Rename + Share + Refresh above a selectable file list.
Parameters
- __namedParameters: SessionEmptyStateProps
Returns Element
Example
```
<SessionEmptyState
  icon={<QAIcon />}
  onCreate={startNew}
  showCreateButton={isOwner}
  labels={{ message: 'No Q&A session open', createButton: 'Start New Session' }}
  filterFileType="qa-session"
  onFileOpen={handleOpenQAFile}
/>
```
- Defined in session-common/components/SessionEmptyState.tsx:28