Restore restriction bypass via key disclosure vulnerability (pgAdmin 4)

pgAdmin versions 9.11 are affected by a Restore restriction bypass via key disclosure vulnerability that occurs when running in server mode and performing restores from PLAIN-format dump files. An attacker with access to the pgAdmin web interface can observe an active restore operation, extract the `\restrict` key in real time, and race the restore process by overwriting the restore script with a payload that re-enables meta-commands using `\unrestrict <key>`. This results in reliable command execution on the pgAdmin host during the restore operation.