Energy Saver Smart 1.2.0

Applied improvements
- Increased plugin version from 1.1 to 1.2.0.
- Renamed the distributable folder/main slug to energy-saver-smart.
- Added plugin headers for Text Domain, Domain Path, Requires at least, Tested up to, and Requires PHP.
- Added translation loading with the new text domain energy-saver-smart.
- Reorganized the plugin into dedicated settings and frontend classes.
- Replaced the old jQuery + setInterval frontend logic with vanilla JavaScript + setTimeout.
- Moved frontend styles into a dedicated CSS file.
- Removed hardcoded asset paths and now load the logo from the plugin URL.
- Added settings sanitization and validation callbacks.
- Preserved existing core option names for easier upgrade compatibility.
- Added new settings: mobile disable, WooCommerce exclusions, excluded URL paths, excluded CSS selectors.
- Prevented the overlay from appearing while users are typing or while audio/video is playing.
- Added accessibility improvements: dialog semantics, keyboard dismissal, visible resume button, reduced-motion support.
- Added uninstall cleanup for plugin options.
- Added Settings shortcut link in the plugins list.
- Updated readme metadata and changelog.
