fix: use valid notification fallback log level

Co-authored-by: jokob-sk <96159884+jokob-sk@users.noreply.github.com>

.github/skills/code-standards/SKILL.md

@@ -24,6 +24,7 @@ description: NetAlertX coding standards and conventions. Use this when writing c
 - follow existing code style and structure, and ensure backward compatibility with existing installations when submitting PRs
 - all code needs to be scalable to handle large networks with thousands of devices (10k+) without performance degradation
 - no inline imports, all imports must be at the top of the file
+- when using `server/logger.py` `mylog()`, only use valid levels: `none`, `minimal`, `verbose`, `debug`, `trace`; invalid levels silently degrade to `none`
 
 
 ## File Length

server/models/notification_instance.py

@@ -421,7 +421,7 @@ def finalize_html(mail_html, preheaders):
         )
     except XMLTokenError as err:
         mylog(
-            "warn",
+            "none",
             f"[Notification] Failed to pretty-print HTML report, sending unindented HTML instead: {err}",
         )
         return mail_html

test/backend/test_notification_templates.py

@@ -334,8 +334,9 @@ class TestConstructNotificationsTemplates(unittest.TestCase):
     # -----------------------------------------------------------------
     # Final HTML escapes preheaders and tolerates indent failures
     # -----------------------------------------------------------------
+    @patch("models.notification_instance.mylog")
     @patch("models.notification_instance.indent")
-    def test_finalize_html_escapes_preheader_and_falls_back(self, mock_indent):
+    def test_finalize_html_escapes_preheader_and_falls_back(self, mock_indent, mock_mylog):
         from models.notification_instance import finalize_html, XMLTokenError
 
         mock_indent.side_effect = XMLTokenError("broken html")
@@ -351,6 +352,10 @@ class TestConstructNotificationsTemplates(unittest.TestCase):
 
         self.assertEqual(final_html, expected_html)
         mock_indent.assert_called_once()
+        mock_mylog.assert_called_once_with(
+            "none",
+            "[Notification] Failed to pretty-print HTML report, sending unindented HTML instead: broken html",
+        )
 
 
 if __name__ == "__main__":