An empty subdomain previously resolved to the domain apex, which would
collide on the root for any unconfigured Traefik port. Treat empty as the
app-name default (matching legacy behaviour); apex is reachable only via the
explicit @ / root sentinel.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Signed-off-by: librelad <librelad@digitalangels.vip>
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