Improve Script Stability: Error Handling, NTP Sync, Wait Behavior, and Package Management

[nmehran]

Changes (closes #68):

• End script immediately on error
• Alternate method to force re-sync of NTP
• Update and upgrade system packages, with lock mitigation support.
• Synchronize node NTPs to ensure time synchronization on nodes
• Add robust wait on "Install Metallb"

[nmehran]

We can further streamline this with:

# Update and upgrade system packages, with lock mitigation support
attempt_limit=10
attempt_delay_seconds=3
for ((attempt=1; attempt<=attempt_limit; attempt++)); do
    if sudo apt-get update && sudo apt-get upgrade -y; then
        echo "Package list updated and packages upgraded successfully."
        break # Success
    elif ((attempt == attempt_limit)); then
        echo "Failed to update and upgrade packages within $attempt_limit attempts."
        exit 1 # Failure after all attempts
    else
        echo "Attempt $attempt of $attempt_limit failed. Retrying in $attempt_delay_seconds seconds..."
        sleep $attempt_delay_seconds
    fi
done