fix: use elif in progress.sh to prevent printing both hours and days estimates

[amathxbt]

Bug

progress.sh uses three independent if blocks for the sync time estimate display:

if [ $MINUTES -le 60 ] ; then
   echo "Sync will complete in minutes"
   echo "Minutes until sync completed: $MINUTES"
fi

if [ $MINUTES -gt 60 ] ; then
   echo "Sync will take hours"
   echo "Hours until sync completed: $HOURS"
fi

if [ $HOURS -gt 24 ] ; then
   echo "Sync will take days"
   DAYS=$((HOURS / 24))
   echo "Days until sync complete: $DAYS"
fi

When $HOURS > 24, both the second and third blocks execute, printing:

Sync will take hours
Hours until sync completed: 30
Sync will take days
Days until sync complete: 1

This is contradictory output — users see both "hours" and "days" simultaneously, making the information confusing and untrustworthy.

Fix

Replace with elif / else so only the most appropriate time unit is shown:

if [ $MINUTES -le 60 ]; then
   echo "Sync will complete in minutes"
   echo "Minutes until sync completed: $MINUTES"
elif [ $HOURS -le 24 ]; then
   echo "Sync will take hours"
   echo "Hours until sync completed: $HOURS"
else
   echo "Sync will take days"
   DAYS=$((HOURS / 24))
   echo "Days until sync complete: $DAYS"
fi