feat(manifest): add externalNumber reference to quote/order/delivery

- Add `external_number NVARCHAR(100)` column to the `manifest` table.
- Thread `externalNumber` through manifestDoc and delivery SQL (list,
  header, create, update).
- Include `externalNumber` in shapeSummary and quote/order/delivery
  create/update/list/getById handlers (optional, clearable on update).
- Update README type definitions and regenerate API/schema docs.

src/store/delivery/update.js

@@ -24,8 +24,9 @@ export default function update(pool) {
    * @param {string} [patch.number] - The new delivery number.
    * @param {string} [patch.date] - The new delivery date.
    * @param {number} [patch.supplierId] - The new supplier id.
+   * @param {string} [patch.externalNumber] - The new external (supplier) reference number.
    * @param {Array<object>} [patch.lines] - The new delivery lines.
-   * @returns {Promise<{id: number, number: string, type: string, entityId: number, date: string, lines: Array<object>}>} The updated delivery.
+   * @returns {Promise<{id: number, number: string, type: string, entityId: number, externalNumber: string|null, date: string, lines: Array<object>}>} The updated delivery.
    * @throws {Error} If the delivery is not found.
    *
    * @example
@@ -43,9 +44,10 @@ export default function update(pool) {
       patch,
       'supplierId',
     );
+    const hasExternalNumber = Object.prototype.hasOwnProperty.call(patch, 'externalNumber');
     const hasLines = Object.prototype.hasOwnProperty.call(patch, 'lines');
 
-    if (!hasNumber && !hasDate && !hasSupplierId && !hasLines) {
+    if (!hasNumber && !hasDate && !hasSupplierId && !hasExternalNumber && !hasLines) {
       throw new Error('Invalid delivery');
     }
 
@@ -99,12 +101,20 @@ export default function update(pool) {
         );
       }
 
+      let externalNumber = summary.externalNumber;
+      if (hasExternalNumber) {
+        externalNumber = patch.externalNumber?.trim?.()
+          ? patch.externalNumber.trim()
+          : null;
+      }
+
       await request(pool, tx)
         .input('id', id)
         .input('companyId', companyId)
         .input('type', DELIVERY_TYPE)
         .input('number', number)
         .input('entityId', supplierId)
+        .input('externalNumber', externalNumber)
         .input('date', date)
         .query(UPDATE_MANIFEST);