Function rollback_string_insert 

pub fn rollback_string_insert(
    system: &RollbackSystem,
    _string_id: u64,
    _string_value: &str,
) -> Result<(), RecoveryError>

Rollback string insertion

String rollback is complex due to deduplication in the string table. Multiple WAL records might reference the same string, so we can’t simply remove it from the table without reference counting.

Current implementation uses a logging-based approach where strings remain in the table for consistency. Future implementation could use reference counting.