Critical fixes:
- Sibling matching now requires BOTH request_number AND search_scope
(previously matched on request_number alone, mixing different people)
- If page 2 has no search_scope, inheritance is skipped (safe default)
- Inherit search_scope from sibling doc during confirm so merge validation works
- Normalize scope values on both sides when checking merge_allowed
- Merge was blocked because page 2 had empty search_scope, making same_scope always false
Georges Haddad
eb79b3781f