SurrealDB lets callers modify records using JSON Patch operations via the `UPDATE … PATCH` statement (and SDK equivalents such as `db.patch()`). One of those operations is `copy`, which duplicates one field's value into another field of the same record. A `PATCH` with an empty `from` — for example, `UPDATE thing:1 PATCH [{ op: 'copy', from: '', path: '/leak' }]` — was treated as "copy the entire record" and duplicated every field, including fields the caller has no permission to read, into the d