- Add formatLastSeen(ms) to format millisecond timestamps into relative
strings (Xs ago, Xm ago, Xh ago, Xd ago, Never for null)
- Add buildOfflineTileHTML(source) to render unreachable device tiles
with Offline badge and last-seen timestamp
- Both functions added after buildAuthTileHTML in app.js
- Both exported via module.exports
- 7 new tests covering export, CSS class, device name, badge, last-seen,
HTML escaping, and null handling
Brian Krabach
e07cf196c6