Point the registry at the namespace that actually exists

The images were tagged gitea.../marc/..., a placeholder that was never
changed and is not a Gitea account, so every push failed with a 404 and
the images had in fact never been published. The registry owner is honey.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

build.sh

@@ -2,7 +2,7 @@
 set -e
 
 REGISTRY="gitea.honeyy.duckdns.org"
-OWNER="${GITEA_OWNER:-marc}"
+OWNER="${GITEA_OWNER:-honey}"
 TAG="${1:-latest}"
 
 FRONTEND_IMAGE="${REGISTRY}/${OWNER}/inknote-web:${TAG}"