scripts/syslog_receiver.py: asyncio UDP server listening on port 5140,
appends raw syslog lines to network-syslog.txt for the Turnstone live
watcher to tail. Requires no root — port 5140 is non-privileged.
scripts/turnstone-syslog-receiver.service: systemd unit for auto-start.
app/ingest/syslog.py: strip optional RFC 3164 <PRI> prefix before
parsing so network-forwarded syslog (OpenWRT logd, Arista EOS, etc.)
is handled correctly without the PRI value breaking the regex.
