fix(restore): drop USE/CREATE DATABASE statements so mysql/mariadb restores target the selected database

[Siumauricio]

Closes #3436

Dumps taken with --databases (or brought from another instance) contain USE \source_db`;— the restore pipeline piped them verbatim intomariadb/mysql <target_db>, so every statement after the USE` executed against the source database instead of the one selected in the restore dialog. In the reported case this overwrote a production database.

The fix inserts a line filter between gunzip and the client for mysql/mariadb restores that drops USE/CREATE DATABASE statements, so the whole dump applies to the database passed on the command line. String values are safe: mysqldump/mariadb-dump escape newlines inside values, so data lines can never start with these keywords.

Verified against a real MariaDB 11 container: before the fix, restoring a --databases dump into dev_db overwrote production_db and left dev_db empty; after the fix, production_db is untouched and dev_db receives the data.

Greptile Summary

This PR prevents MySQL and MariaDB restores from redirecting writes to a database named inside the dump.

• Adds a case-insensitive line filter that removes USE and CREATE DATABASE statements from MySQL/MariaDB restore streams.
• Adds tests covering statement removal, preservation of ordinary SQL and string values, and engine-specific pipeline wiring.

Confidence Score: 5/5

The PR appears safe to merge, with no actionable changed-code defects identified.

The filter covers the database-selection statements emitted by the supported MariaDB dump path, remains a harmless pass-through for ordinary SQL, and is limited to MySQL and MariaDB restores.

_{Reviews (1): Last reviewed commit: "fix(restore): drop USE/CREATE DATABASE s..." | Re-trigger Greptile}

Context used:

• Knowledge Base — Backups and Schedules