[UI] Suggested pricing (#10867)

* Refactor NumberField into separate component

* Add helper func to ensure a number is a number

* Use placeholder value for suggested sale price

* Fix for auto-fill

* Tweak price calculation

* Add UI testing for sales order price breaks

* Fix aria label name

* Annotate price breaks to supplier part

* Fetch price break data

* Support price breaks for purchase order pricing

* Fix required to prevent circular imports

* Add playwright tests for purchase order price breaks

* Bump API version

* Re-add output options for SupplierPriceBreakList

* Revert change

* Simplify unit test

src/frontend/tests/pages/pui_sales_order.spec.ts

@@ -279,3 +279,45 @@ test('Sales Orders - Duplicate', async ({ browser }) => {
   await page.getByText('Complete').first().waitFor();
   await page.getByText('2 / 2').waitFor();
 });
+
+/**
+ * Test auto-calculation of price breaks on sales order line items
+ */
+test('Sales Orders - Price Breaks', async ({ browser }) => {
+  const page = await doCachedLogin(browser, {
+    url: 'sales/sales-order/14/line-items'
+  });
+
+  await page
+    .getByRole('button', { name: 'action-button-add-line-item' })
+    .click();
+  await page.getByLabel('related-field-part').fill('software');
+  await page.getByRole('option', { name: 'Software License' }).click();
+
+  const priceBreaks = {
+    1: 123,
+    2: 123,
+    10: 104,
+    49: 104,
+    56: 96,
+    104: 78
+  };
+
+  for (const [qty, expectedPrice] of Object.entries(priceBreaks)) {
+    await page.getByLabel('number-field-quantity').fill(qty);
+
+    await expect(
+      page.getByRole('textbox', { name: 'number-field-sale_price' })
+    ).toHaveAttribute('placeholder', expectedPrice.toString(), {
+      timeout: 500
+    });
+  }
+
+  // Auto-fill the suggested sale price
+  await page.getByLabel('field-sale_price-accept-placeholder').click();
+
+  // The sale price field should now contain the suggested value
+  await expect(
+    page.getByRole('textbox', { name: 'number-field-sale_price' })
+  ).toHaveValue('78', { timeout: 500 });
+});