Speedup encoding check by executing it as a fallback on execute_statements

[sejas]

Let's check the encoding only if the query fails.

Testing instructions:

• Import a file with a wrong encoding.
• Observe in the logs:

Importing /var/folders/_x/rbv26n3925q_01dbs4jzd8t80000gn/T/studio_backupUNLJzi/wp_aioseo_notifications.sql
SQLite import stdout: Converted ecoding for statement: INSERT INTO `wp_aioseo_notifications` (`id`, `slug`, `addon`, `title`, `content`, `type`, `level`, `notification_id`, `notification_name`, `start`, `end`, `button1_label`, `button1_action`, `button2_label`, `button2_action`, `dismissed`, `new`, `created`, `updated`) VALUES (4,'68b5184c74ce5',NULL,'Introducing Site Audit in AIOSEO 4.8.6','<p>Tired of guessing why your website isn稚 ranking higher? Or frustrated by SEO tools that give you too much data but no clear answers?</p>\n\n<p>We致e supercharged our SEO Analyzer to give you crystal-clear insights and action steps羊ight inside your WordPress dashboard!</p>\n\n<p>Now you can:</p>\n\n<p>? Scan your <strong>entire site</strong> for common SEO issues.</p>\n\n<p>? View issues <strong>page-by-page</strong> or <strong>by issue type</strong>.</p>\n\n<p>? <strong>Get instant tooltips</strong>, 1-click fixes, and quick keyword additions.</p>\n\n<p>? <strong>Track progress</strong> with satisfying visual checkmarks.</p>\n\n<p>Update to AIOSEO 4.8.6 today and take the guesswork out of SEO!</p>','success','[\"4-x\",\"lite\"]',1298,NULL,'2025-08-27 00:00:00',NULL,'Learn More','https://aioseo.com/site-audit-announcement/?utm_source=WordPress&utm_medium=plugin-notification&utm_campaign=486-v4-x-lite','Get AIOSEO Pro','https://aioseo.com/lite-upgrade/?utm_source=WordPress&utm_medium=plugin-notification&utm_campaign=486-v4-x-lite',0,0,'2025-09-01 03:51:40','2025-09-21 19:12:01')
Success: Imported from 'studio-backup-sql-2025-10-10-11-30-02.sql'.

• Confirm the sql dump was imported correctly

[JanJakes]

@sejas Looks good! Feel free to merge it into my branch.