fix(invoice): detect pickup via missing shippingAddress (real signal for built-in 'Shop location' rate)

Reproduced against real dev order #1032: the built-in 'Shop location'
shipping rate sets neither a pickup keyword nor deliveryCategory:

  shippingLine: { title: 'Shop location', code: 'Shop location',
                  source: 'shopify', deliveryCategory: null }
  shippingAddress: null
  requiresShipping: true

So neither v2 (string regex on title/code) nor v3 (deliveryCategory)
caught it. The robust signal is 'requiresShipping && shippingAddress
== null': Shopify rejects checkout for a normal shipping order without
an address, so this combination is conclusive proof of pickup.

- Query Order.requiresShipping (only needs read_orders).
- detectPickup() now treats missing-address-but-requires-shipping as the
  primary signal; deliveryCategory + title/code regex remain as
  fallbacks for Local-Pickup-app installs and custom rates.
- New fixture buildShopLocationPickupOrder() in render-sample.ts
  mirrors order #1032 exactly so we never regress on this shape.

scripts/render-sample.ts

@@ -136,6 +136,7 @@ function buildAtB2BOrder(): RawOrderForInvoice {
     displayFinancialStatus: "PENDING",
     paymentGatewayNames: ["manual"],
     taxesIncluded: false,
+    requiresShipping: true,
     discountCodes: [],
     customer: {
       firstName: "Lukas",
@@ -329,6 +330,28 @@ function buildCategoryOnlyPickupOrder(): RawOrderForInvoice {
   return o;
 }
 
+/** Pickup variant matching a REAL observed order on
+ *  linumiq-dev.myshopify.com (#1032): Shopify's built-in "Shop location"
+ *  rate. NO "pickup" string anywhere, deliveryCategory is `null`, and
+ *  shippingAddress is also `null` — detection must rely on
+ *  `requiresShipping && shippingAddress == null`. */
+function buildShopLocationPickupOrder(): RawOrderForInvoice {
+  const o = buildAtB2BOrder();
+  o.shippingLine = {
+    title: "Shop location",
+    code: "Shop location",
+    source: "shopify",
+    carrierIdentifier: null,
+    deliveryCategory: null,
+    originalPriceSet: { shopMoney: { amount: "0.00", currencyCode: "EUR" } },
+    discountedPriceSet: { shopMoney: { amount: "0.00", currencyCode: "EUR" } },
+    taxLines: [],
+  };
+  o.shippingAddress = null;
+  o.requiresShipping = true;
+  return o;
+}
+
 // ------------------------------------------------------------------
 // Run assertions
 // ------------------------------------------------------------------
@@ -655,6 +678,21 @@ async function main() {
   assert("shippingMethod cleared in category-only pickup",
     categoryPickupVm.shippingMethod == null);
 
+  // Real-world "Shop location" pickup (matches dev order #1032): no
+  // "pickup" keyword anywhere, deliveryCategory null, shippingAddress null.
+  // The only signal is `requiresShipping && !shippingAddress`.
+  const shopLocPickupVm = composeInvoice({
+    order: buildShopLocationPickupOrder(),
+    settings: settings as never,
+    invoiceNumber: "RE-1034",
+  });
+  assert("isPickup detected from missing shippingAddress (Shop location rate)",
+    shopLocPickupVm.isPickup);
+  assertEq("pickupLocationName from shippingLine.title for Shop location",
+    shopLocPickupVm.pickupLocationName, "Shop location");
+  assert("shippingMethod cleared for Shop location pickup",
+    shopLocPickupVm.shippingMethod == null);
+
   // Fallback: when footerNoteEn is empty, English uses the German note.
   console.log("• Footer note fallback (en → de when EN empty)");
   const settingsNoEn = { ...(settings as object), footerNoteEn: "" } as never;