The rollup and the backup check in once, when they end, with the run's duration

A start and a finish sent seconds apart can reach Sentry in either order,
and a start that lands second is never closed, so a fast rollup could be
reported as a timeout on a night it succeeded. Hnefatafl's monitor did so
nine nights in fifteen on the shared host. One check-in at the end cannot
race; a run that hangs sends nothing and is marked missed. Installed on
the host by hand; the next deploy installs the same files.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GwFKMuQnPAEHJ5yA1q4orh

deploy/wizwar-backup.sh

@@ -11,7 +11,12 @@ STAMP=$(date +%Y-%m-%d)
 # Sentry Crons check-in: /root/.wizwar-sentry-cron holds the check-in URL
 # (auto-creates the monitor on first ping). Absent file = no check-ins.
 CRON_URL=$(cat /root/.wizwar-sentry-cron 2>/dev/null || true)
-checkin() { [ -n "$CRON_URL" ] && curl -sf -o /dev/null "$CRON_URL?status=$1" || true; }
+# One check-in, when the run ends, carrying its duration: a start and a
+# finish sent seconds apart can reach Sentry in either order, and a start
+# that lands second is never closed. A run that never ends sends nothing,
+# and Sentry marks the night missed.
+START=$SECONDS
+checkin() { [ -n "$CRON_URL" ] && curl -sf -o /dev/null "$CRON_URL?status=$1&duration=$((SECONDS - START))" || true; }
 
 if grep -q CHANGE_ME /root/.config/rclone/rclone.conf; then
   echo "$(date -Is) skipped: Spaces credentials not configured yet" >> "$LOG"
@@ -20,7 +25,6 @@ fi
 
 {
   echo "=== $(date -Is) backup start"
-  checkin in_progress
   if rclone sync "$SRC" "spaces:$BUCKET/wizwar/current" 2>&1 &&
      rclone copy "$SRC" "spaces:$BUCKET/wizwar/snapshots/$STAMP" 2>&1; then
     checkin ok