fix(delivery-notes): stop flagging duplicates once a copy is zeroed

The "Possible duplicate receipts" warning grouped posted receipts by
document number regardless of what they book. After the office corrects
the duplicate copy of a slip to 0 (receipts are delivery evidence and
cannot be deleted), the pair kept showing.

Receipts whose lines all total 0 are now left out of the grouping: a copy
that books nothing cannot double-count. Receipts with no lines are still
flagged, and pairs where both copies book quantity still show.

Clears the four Raumix DQ0010116/0472/0051/0092 groups on MEGCPO9165.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/app/dashboard/financial/delivery-notes/page.tsx

@@ -107,7 +107,7 @@ export default async function DeliveryNotesPage({
     }));
 
   const posForAssign: PoChoice[] = buildPoChoices(pos, sites);
-  const possibleDuplicates = possibleDuplicateReceiptGroups(dns, pos);
+  const possibleDuplicates = possibleDuplicateReceiptGroups(dns, pos, itemsByDn);
 
   // KPIs describe the full site-scoped set of delivery notes, not the rows
   // the operator has filtered in the table.

src/lib/dn-pipeline/possible-duplicate-receipts.test.ts

@@ -37,6 +37,18 @@ describe("possible duplicate posted receipts", () => {
     ]);
   });
 
+  it("stops flagging a pair once the duplicate copy has been corrected to zero", () => {
+    const rows = [receipt("kept", "s", "DQ0010116"), receipt("zeroed", "s", "DQ0010116")];
+    const booked = new Map([["kept", { count: 1, total: 30.26 }], ["zeroed", { count: 1, total: 0 }]]);
+    expect(possibleDuplicateReceiptGroups(rows, [], booked)).toEqual([]);
+  });
+
+  it("still flags receipts that have no lines, and pairs where both copies still book quantity", () => {
+    const rows = [receipt("a", "s", "DQ1"), receipt("b", "s", "DQ1"), receipt("c", "s", "DQ2"), receipt("d", "s", "DQ2")];
+    const booked = new Map([["a", { count: 1, total: 30 }], ["b", { count: 1, total: 30 }]]);
+    expect(possibleDuplicateReceiptGroups(rows, [], booked).map((g) => g.receipts.map((r) => r.id))).toEqual([["a", "b"], ["c", "d"]]);
+  });
+
   it("also flags an invoice explicitly referencing an already posted delivery", () => {
     const invoice = receipt("invoice", "s", "INV1");
     invoice.raw_ocr_data.documentReferences.push("DN1");

src/lib/dn-pipeline/possible-duplicate-receipts.ts

@@ -14,14 +14,27 @@ export type PossibleDuplicateReceiptGroup = { key: string; receipts: DuplicateRe
 const object = (value: unknown): Record<string, unknown> => value && typeof value === "object" && !Array.isArray(value) ? value as Record<string, unknown> : {};
 const text = (value: unknown): string => typeof value === "string" ? value : "";
 
-/** Informational only: callers pass site-scoped receipts; values stay untouched. */
+/**
+ * Informational only: callers pass site-scoped receipts; values stay untouched.
+ *
+ * `bookedQty` (receipt id → total qty_received over its lines), when given,
+ * leaves out receipts whose lines have all been corrected to zero: a copy
+ * that books nothing cannot double-count, so once the office has zeroed the
+ * duplicate copy the pair stops being flagged. Receipts with no lines at all
+ * are kept, because nothing shows they were reviewed.
+ */
 export function possibleDuplicateReceiptGroups(
   receipts: readonly ReceiptReviewRecord[],
   pos: readonly ReceiptPoLookup[] = [],
+  bookedQty?: ReadonlyMap<string, { count: number; total: number }>,
 ): PossibleDuplicateReceiptGroup[] {
   const poById = new Map(pos.map((po) => [po.id, po]));
-  const posted: ReceiptReviewRecord[] = receipts.filter((receipt) => Boolean(text(receipt.posted_at)) || receipt.is_verified === true ||
-    ["auto-verified", "manual-verified"].includes(text(receipt.processing_status))).map((receipt) => {
+  const zeroed = (receipt: ReceiptReviewRecord) => {
+    const booked = bookedQty?.get(receipt.id);
+    return Boolean(booked && booked.count > 0 && booked.total === 0);
+  };
+  const posted: ReceiptReviewRecord[] = receipts.filter((receipt) => !zeroed(receipt) && (Boolean(text(receipt.posted_at)) || receipt.is_verified === true ||
+    ["auto-verified", "manual-verified"].includes(text(receipt.processing_status)))).map((receipt) => {
       const expanded = object(receipt.expand);
       const expandedPo = object(expanded.purchase_order);
       const po = poById.get(text(receipt.purchase_order));