Monitor SSL certificate expiry with Google Sheets and SMTP email alerts

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Who is this for? DevOps engineers, sysadmins, and website owners who manage multiple domains and need proactive SSL certificate expiration monitoring without manual checks. What it does Automatically monitors SSL certificates across multiple domains, tracks expiration status in a Google Sheet dashboard, and sends beautifully formatted HTML email alerts before certificates expire. ✅ No API rate limits — Uses direct OpenSSL commands, so you can scan unlimited domains with zero API costs or res