added enums for status constants/fixed status not updating

src/monitor_utils/constants.py

@@ -6,6 +6,7 @@ and the expected error tuple used for known-failure handling.
 """
 
 import asyncio
+from enum import Enum
 from json import JSONDecodeError
 
 import aiohttp
@@ -58,10 +59,6 @@ BUCKET_WEBHOOK_MAP = {
     90: "90-100",
     "price_drop": "40-49",
 }
-STATUS_PENDING = "pending"
-STATUS_SENT = "sent"
-STATUS_SKIPPED = "skipped"
-STATUS_FAILED = "failed"
 
 EXPECTED_TASK_ERRORS = (
     RequestsError,
@@ -72,3 +69,12 @@ EXPECTED_TASK_ERRORS = (
     PyMongoError,
     JSONDecodeError,
 )
+
+
+class ProductStatus(str, Enum):
+    """Lifecycle status for a monitored product document."""
+
+    PENDING = "pending"
+    SENT = "sent"
+    SKIPPED = "skipped"
+    FAILED = "failed"