Expose current upstream address in /stats response. Dashboard footer
now shows "Upstream: x.x.x.x:53" — updates live when the network
watcher swaps the upstream.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
When numa install is active, scutil --dns only returns 127.0.0.1.
Previously fell back to 9.9.9.9 (Quad9) which fails on networks
that block external DNS. Now reads DHCP-provided DNS from
ipconfig getpacket en0/en1 as intermediate fallback before Quad9.
Tested on a network that blocks 8.8.8.8, 9.9.9.9, 1.1.1.1 but
allows ISP DNS (213.154.124.25) — Numa now auto-detects and uses it.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Always detect network changes (LAN IP, upstream, peers) regardless
of upstream config. LAN IP is now tracked in ServerCtx and updated
every 30s — multicast announcements use the current IP instead of
the startup IP. Upstream re-detection still only runs when
auto-detected. Peer flush triggers on any network change.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Upstream DNS was resolved once at startup and never updated. Switching
Wi-Fi networks made all queries fail until restart.
Now spawns a background task (every 30s) that re-runs system DNS
discovery and swaps the upstream atomically if it changed. Also flushes
stale LAN peers from the old network on change.
Only activates when upstream is auto-detected (not explicitly configured).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
