Switch mgmt-VLAN DHCP advertised a default gateway (192.168.88.1) that
stole mamba's default route from WiFi, cutting the netbird underlay to
askari. Fixed client-side with never-default/high-metric/ignore-auto-dns
on the wired NetworkManager profile; WiFi stays default, tunnel holds.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
