ci: rename rolling release tag dev -> dev-latest

A release tag named "dev" collides with the dev branch, making refs
ambiguous ("refname 'dev' is ambiguous") and breaking git push/checkout.
Publish the rolling build to tag "dev-latest" instead; pi-update.sh pulls
from there.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

scripts/pi-update.sh

@@ -24,7 +24,7 @@ REPO="${REPO:-CubeCraft-Creations/remote-rig}"
 DEPLOY_DIR="/opt/remoterig"
 DEPLOY_PATH="${DEPLOY_PATH:-$DEPLOY_DIR/remoterig}"
 SERVICE="${SERVICE:-remoterig}"
-TAG="dev"
+TAG="dev-latest"
 DL="$GITEA_BASE/$REPO/releases/download/$TAG"
 VERSION_FILE="$DEPLOY_DIR/VERSION"