🚀 chore(ui): Refactor UpstreamRatioSync with conflict-modal component, performance hooks & cleanup (#1286) WHAT’S NEW • Extracted reusable ConflictConfirmModal for clearer JSX hierarchy • Added detailed conflict detection & confirmation flow before syncing options • Refactored state-heavy callbacks (`selectValue`, `performSync`) with `useCallback` to avoid unnecessary renders • Introduced build-time constants (later removed unused export) and unified helper utilities • Ensured final ratios are rebuilt accurately before API `PUT`, fixing “value not updated” bug • Enhanced UI hints: warning icon on conflict, multiline billing info, mobile-friendly modal size • General code cleanup: removed dead variables, adopted early returns, improved comments WHY Improves maintainability, user clarity when billing-type collisions occur, and guarantees data consistency after synchronisation.
