Turn off travelling so home shows the between-trips state everywhere

travelling was only set to false in user/env/localhost/config/site.yaml,
which Grav reads only when the request hostname is literally "localhost",
and which is git-ignored. So the home page still rendered Denmark 2026 as
an active trip on every other hostname, and the setting could never reach
production. Set it in the tracked config instead.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

config/site.yaml

@@ -6,5 +6,5 @@ metadata:
   description: 'Into the East — travel journal'
 description: 'A travel blog by Mischa'
 active_trip: /trips/denmark-2026
-travelling: true
+travelling: false
 owner_username: mischa