- Add Packets.get_other_ssids/1 to query other SSIDs for a base callsign
- Show other SSIDs in MapLive sidebar with track and info link buttons
- Clicking an SSID tracks it on the map (zooms, shows marker, updates URL)
- Refactor InfoLive.Show to use shared Packets.get_other_ssids/1
- Remove web-layer dependency from Packets context (no more
AprsmeWeb.TimeHelpers calls from data layer)
- Return raw received_at DateTime instead of pre-formatted timestamp maps
- Format timestamps in the view layer where they belong