Refactor register_import and register_export tables into one table

The register_id and timestamp are always the same. Because really it's one reading split into two parts import/export.
We should have these as one table.

<img width="503" height="173" alt="Image" src="https://github.com/user-attachments/assets/9d007c87-bcb5-4918-999b-6deecff0cbb2" />