Replace webhook manager datetime.utcnow calls (#1499)

Co-authored-by: ghreprimand <203024559+ghreprimand@users.noreply.github.com>

src/webhook_manager.py

@@ -7,7 +7,7 @@ import ipaddress
 import json
 import logging
 import re
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import Optional
 from urllib.parse import urlparse
 
@@ -37,6 +37,11 @@ _PRIVATE_NETWORKS = [
 ]
 
 
+def _utcnow() -> datetime:
+    """Return naive UTC for existing DB columns while avoiding datetime.utcnow()."""
+    return datetime.now(timezone.utc).replace(tzinfo=None)
+
+
 def _ip_is_private(addr: ipaddress._BaseAddress) -> bool:
     # If the address is IPv4-mapped IPv6, extract and evaluate the embedded IPv4
     if isinstance(addr, ipaddress.IPv6Address) and addr.ipv4_mapped is not None:
@@ -203,7 +208,7 @@ class WebhookManager:
             logger.warning(f"Webhook {webhook_id} has invalid URL, skipping: {e}")
             return
 
-        body = json.dumps({"event": event, "timestamp": datetime.utcnow().isoformat(), "data": payload})
+        body = json.dumps({"event": event, "timestamp": _utcnow().isoformat(), "data": payload})
         headers = {
             "Content-Type": "application/json",
             "X-Odysseus-Event": event,
@@ -217,7 +222,7 @@ class WebhookManager:
         try:
             resp = await self._client.post(url, content=body, headers=headers)
             db.query(Webhook).filter(Webhook.id == webhook_id).update({
-                "last_triggered_at": datetime.utcnow(),
+                "last_triggered_at": _utcnow(),
                 "last_status_code": resp.status_code,
                 "last_error": None,
             })
@@ -226,7 +231,7 @@ class WebhookManager:
             logger.warning(f"Webhook delivery failed for {webhook_id}")
             try:
                 db.query(Webhook).filter(Webhook.id == webhook_id).update({
-                    "last_triggered_at": datetime.utcnow(),
+                    "last_triggered_at": _utcnow(),
                     "last_status_code": None,
                     "last_error": sanitize_error(str(e)),
                 })