feat(orders): add order/item duplicate-detection fields to Order type

src/lib/types.ts

@@ -669,6 +669,37 @@ export interface Order extends BaseRecord {
    *  orders-service.ts:253). delivery_note_number is immutable once
    *  assigned, so copying carries no staleness risk. */
   potential_delivery_note_number?: string;
+  /**
+   * Relation to another order sharing the exact same `order_number`,
+   * of any status, no time limit. Set by
+   * suggestOrderNumberDuplicate (order-number-duplicate-link-service.ts).
+   * Visibility only — free-text custom order numbers (customer PO
+   * refs, "NO-REF" placeholders) are allowed to repeat by design; this
+   * flag exists so the operator can eyeball whether a given repeat was
+   * intentional.
+   */
+  order_number_duplicate?: string;
+  /** True once suggestOrderNumberDuplicate has run for this order —
+   *  distinguishes "checked, no match" from "never checked." */
+  order_number_duplicate_checked?: boolean;
+  /**
+   * Relation to another order whose line items (description +
+   * quantity) exactly match this order's, for the same company,
+   * within the last 60 days, regardless of either order's status. Set
+   * by suggestOrderDuplicate (order-order-duplicate-link-service.ts).
+   * Visibility only.
+   */
+  potential_duplicate_order?: string;
+  /** Denormalized copy of the matched order's order_number — same
+   *  reasoning as potential_delivery_note_number: lets the list pill
+   *  render without a second expand. */
+  potential_duplicate_order_number?: string;
+  /** 1 if potential_duplicate_order is set, 0 otherwise. */
+  duplicate_order_match_confidence?: number;
+  /** "exact_items_same_company" | "no_match" */
+  duplicate_order_match_method?: string;
+  /** True once suggestOrderDuplicate has run for this order. */
+  duplicate_order_matching_attempted?: boolean;
   is_repair_order: boolean;
   /**
    * Sales rep handling this order. Free-text — auto-populated from the