MainWP Domain Monitor Extension 5.3

* Fixed: Unchanged domains no longer trigger unnecessary WHOIS lookups.
* Fixed: Improved handling of unknown domain extensions and WHOIS connection failures.
* Added: Database schema validation to help ensure required monitoring data is properly configured.
* Updated: Domain monitoring now automatically includes newly connected sites.
* Updated: Scheduled monitoring now synchronizes monitored sites when checks begin or settings are saved.
* Updated: Improved validation of monitoring records before they are created or updated.

* Fixed: Corrected domain status calculations to ensure domain health and summary data display accurately.
* Fixed: Improved handling of missing domain records to prevent errors when domain data is unavailable.
* Fixed: Updated missing expiration date handling so unavailable expiry data is treated consistently.
* Fixed: Corrected documentation links and minor text typos in the Domain Monitor interface.
* Updated: Improved dashboard display for unscanned sites with clearer icons, text, row highlighting, and consistent "N/A" values.
* Updated: Refreshed Domain Monitor settings layout with clearer section headings and subheadings for improved readability.
* Updated: Removed redundant tooltip attributes from toggle containers for cleaner and more consistent interface markup.
* Updated: Optimized plugin initialization timing to improve compatibility and reliability within the WordPress environment.