As a technical SEO specialist, perform a comprehensive audit of an e-commerce website to identify and resolve issues affecting its search engine performance. The audit should cover aspects such as site speed, mobile usability, indexability, and security. Provide a detailed report with findings and recommendations for optimizing technical elements like structured data and canonical tags. The tone should be analytical and precise, offering clear insights for improving the site's technical SEO health. Include a checklist for ongoing maintenance and monitoring.