feat(drafts): DB drafts with deferred numbering — create-as-draft (no number), assign number on finalize (offers/invoices/issued-orders)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/services/numbering.service.ts

@@ -413,6 +413,76 @@ export async function previewIssuedOrderNumber(
   return { number, next_number: number };
 }
 
+/**
+ * Deferred-assign helpers — used when a draft (number-less) document is
+ * finalized. Each runs inside a transaction (the caller's `tx` if provided,
+ * otherwise a fresh `prisma.$transaction`), reads the row's current number, and:
+ *   - if it is already set (non-null/non-empty), returns it unchanged
+ *     (idempotent — finalizing twice never re-numbers / double-consumes); else
+ *   - calls the existing per-type generator (which consumes the sequence under
+ *     the same row lock) and writes the number onto the row.
+ * The sequence is consumed exactly once, atomically with the row write.
+ */
+export async function assignOfferNumber(
+  id: number,
+  tx?: TxClient,
+): Promise<string> {
+  const run = async (client: TxClient): Promise<string> => {
+    const row = await client.quotations.findUnique({
+      where: { id },
+      select: { quotation_number: true },
+    });
+    if (row?.quotation_number) return row.quotation_number;
+    const number = await generateOfferNumber(client);
+    await client.quotations.update({
+      where: { id },
+      data: { quotation_number: number },
+    });
+    return number;
+  };
+  return tx ? run(tx) : prisma.$transaction(run);
+}
+
+export async function assignInvoiceNumber(
+  id: number,
+  tx?: TxClient,
+): Promise<string> {
+  const run = async (client: TxClient): Promise<string> => {
+    const row = await client.invoices.findUnique({
+      where: { id },
+      select: { invoice_number: true },
+    });
+    if (row?.invoice_number) return row.invoice_number;
+    const { number } = await generateInvoiceNumber(undefined, client);
+    await client.invoices.update({
+      where: { id },
+      data: { invoice_number: number },
+    });
+    return number;
+  };
+  return tx ? run(tx) : prisma.$transaction(run);
+}
+
+export async function assignIssuedOrderNumber(
+  id: number,
+  tx?: TxClient,
+): Promise<string> {
+  const run = async (client: TxClient): Promise<string> => {
+    const row = await client.issued_orders.findUnique({
+      where: { id },
+      select: { po_number: true },
+    });
+    if (row?.po_number) return row.po_number;
+    const { number } = await generateIssuedOrderNumber(undefined, client);
+    await client.issued_orders.update({
+      where: { id },
+      data: { po_number: number },
+    });
+    return number;
+  };
+  return tx ? run(tx) : prisma.$transaction(run);
+}
+
 /** Release an issued-order number back to the pool (decrement if highest). */
 export async function releaseIssuedOrderNumber(
   year?: number,