Add Create Test Shipment (Email SKU) for testing the return-label flow, plus test-mode/store_id investigation notes

Adds synthetic source="test" tickets (create_test_shipment_order/delete_test_shipments)
carrying a company's real emailed-return-label SKU, so Step 1/Step 2 can be exercised
against the sandbox without a real JIRA ticket or risking a real customer's. Gated to
Test Mode - the same flow against production would create a real paid shipment.

CLAUDE.md also captures this session's ShipStation sandbox findings: store_id is
schema-optional but empirically required for label visibility, the newer ship15 web UI's
URL is NOT the se- store ID (confirmed via direct probe - different failure shape than a
wrong-but-well-formed ID), and two separate test stores/carriers are needed per company,
mirroring production.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

app/ui/main_window.py

@@ -27,6 +27,7 @@ from PyQt6.QtWidgets import (
     QTabWidget,
     QFileDialog,
     QDialog,
+    QInputDialog,
 )
 
 from app import config
@@ -53,6 +54,8 @@ from app.workers import (
     save_dummy_outbound_label_id,
     save_pack_data,
     reset_local_database,
+    create_test_shipment_order,
+    delete_test_shipments,
 )
 
 
@@ -184,6 +187,24 @@ class MainWindow(QMainWindow):
         create_test_warehouses_action.triggered.connect(self._on_create_test_warehouses_clicked)
         data_menu.addAction(create_test_warehouses_action)
 
+        data_menu.addSeparator()
+
+        create_test_shipment_action = QAction("Create Test Shipment (Email SKU)...", self)
+        create_test_shipment_action.setStatusTip(
+            "Test Mode only - creates a synthetic ticket carrying that company's emailed-"
+            "return-label SKU, so Create Return Label can be run against it in the sandbox"
+        )
+        create_test_shipment_action.triggered.connect(self._on_create_test_shipment_clicked)
+        data_menu.addAction(create_test_shipment_action)
+
+        delete_test_shipments_action = QAction("Delete Test Shipments...", self)
+        delete_test_shipments_action.setStatusTip(
+            "Removes every synthetic ticket created by Create Test Shipment - real JIRA "
+            "tickets are not affected"
+        )
+        delete_test_shipments_action.triggered.connect(self._on_delete_test_shipments_clicked)
+        data_menu.addAction(delete_test_shipments_action)
+
         orders_menu = menu_bar.addMenu("&Orders")
 
         self._pack_ticket_action = QAction("Pack Ticket", self)
@@ -386,6 +407,63 @@ class MainWindow(QMainWindow):
 
         QMessageBox.information(self, "Create Test Warehouse(s)", "\n".join(lines))
 
+    def _on_create_test_shipment_clicked(self) -> None:
+        if not config.is_shipstation_test_mode():
+            QMessageBox.information(
+                self,
+                "Test Mode is off",
+                "Turn on ShipStation Test Mode first (Data menu). This ticket is meant "
+                "to be run through Create Return Label against the sandbox account, not "
+                "production - a real store_id/carrier under production settings would "
+                "create an actual, paid shipment to a fake address.",
+            )
+            return
+
+        company, ok = QInputDialog.getItem(
+            self,
+            "Create Test Shipment",
+            "Company (picks that company's configured emailed-return-label SKU):",
+            ["Signify Health", "Oak Street Health"],
+            editable=False,
+        )
+        if not ok:
+            return
+
+        try:
+            order = create_test_shipment_order(company)
+        except ValueError as exc:
+            QMessageBox.critical(self, "Could not create test shipment", str(exc))
+            return
+
+        self._refresh_everything()
+        QMessageBox.information(
+            self,
+            "Test Shipment Created",
+            f"Created {order.ticket_number} ({company}, SKU {order.skus[0]}) on the "
+            "Active tab.\n\n"
+            "Select it there and use Create Return Label to run Step 1 (dummy "
+            "shipment) and Step 2 (return label) against the sandbox account, the "
+            "same code path a real ticket would use.\n\n"
+            "Use Delete Test Shipments (Data menu) to clean it up afterward.",
+        )
+
+    def _on_delete_test_shipments_clicked(self) -> None:
+        confirm = QMessageBox.question(
+            self,
+            "Delete Test Shipments",
+            "Removes every synthetic ticket created by Create Test Shipment "
+            "(ticket numbers starting with TEST-EMAIL-). Real JIRA tickets are not "
+            "affected.\n\nContinue?",
+            QMessageBox.StandardButton.Yes | QMessageBox.StandardButton.No,
+            QMessageBox.StandardButton.No,
+        )
+        if confirm != QMessageBox.StandardButton.Yes:
+            return
+
+        count = delete_test_shipments()
+        self._refresh_everything()
+        QMessageBox.information(self, "Delete Test Shipments", f"Deleted {count} test shipment(s).")
+
     def _on_order_double_clicked(self, order) -> None:
         dialog = OrderDetailDialog(order, self)
         dialog.exec()