@spec parse(String.t()) :: map()

Parse an APRS item report, data type indicator included.

The name runs to the ! (live) or _ (killed) status byte, and the rest is parsed as an uncompressed or compressed position followed by the shared comment pipeline. Returns :item_name/:itemname, :live_killed, :alive and the position fields; a report whose name cannot be delimited comes back as :raw_data alone.