Add shopper accounts, reviews, tracking, and seed_demo (#9)

Closes #9. Shop-gated buyer accounts, purchase reviews, Stripe customer ids, shipment tracking, slim public contact form, and a template-neutral seed_demo command.

site/shipping/models.py

@@ -11,6 +11,18 @@ class Shipment(UUIDPrimaryKeyModel, TimeStampedModel):
         LABELED = "labeled", "Labeled"
         VOID = "void", "Void"
 
+    class TrackingStatus(models.TextChoices):
+        UNKNOWN = "unknown", "Unknown"
+        PRE_TRANSIT = "pre_transit", "Pre-transit"
+        IN_TRANSIT = "in_transit", "In transit"
+        OUT_FOR_DELIVERY = "out_for_delivery", "Out for delivery"
+        DELIVERED = "delivered", "Delivered"
+        AVAILABLE_FOR_PICKUP = "available_for_pickup", "Available for pickup"
+        RETURN_TO_SENDER = "return_to_sender", "Return to sender"
+        FAILURE = "failure", "Exception"
+        CANCELLED = "cancelled", "Cancelled"
+        ERROR = "error", "Error"
+
     order = models.ForeignKey(Order, on_delete=models.PROTECT, related_name="shipments")
     status = models.CharField(
         max_length=16, choices=Status.choices, default=Status.DRAFT
@@ -18,6 +30,16 @@ class Shipment(UUIDPrimaryKeyModel, TimeStampedModel):
     carrier = models.CharField(max_length=32, blank=True)
     service = models.CharField(max_length=64, blank=True)
     tracking_number = models.CharField(max_length=64, blank=True)
+    tracking_status = models.CharField(
+        max_length=32,
+        choices=TrackingStatus.choices,
+        default=TrackingStatus.UNKNOWN,
+        blank=True,
+    )
+    tracking_url = models.URLField(blank=True)
+    tracker_id = models.CharField(max_length=255, blank=True)
+    tracking_events = models.JSONField(default=list, blank=True)
+    last_tracked_at = models.DateTimeField(null=True, blank=True)
     label_url = models.URLField(blank=True)
     rate_amount = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True)
     currency = models.CharField(max_length=8, default="usd")