- Merge notes + time entries into single chronological timeline
- Time entries: blue clock icon, hours badge, resource name, summary
- Human notes: green user icon, creator name, title + body
- System notes (noteType 13/91/93/94/99/101): bot icon, dimmed, hidden by default
- 'Show/Hide system notes' toggle with count badge appears only when system notes exist
- Both data sources fetched in parallel on first expand, cached for session