feat(errors): introduce AuthenticationError and update failure classification (#274)

Author: snowfox1003

core/errors.py

@@ -11,6 +11,10 @@
 from enum import Enum
 
 
+class AuthenticationError(RuntimeError):
+    """Raised when collector credentials are rejected (HTTP 401/403 or equivalent)."""
+
+
 class CollectorFailureCategory(str, Enum):
     """High-level failure bucket for collector runs."""
 
@@ -183,6 +187,8 @@ def classify_failure(exc: BaseException) -> CollectorFailureCategory:
         return CollectorFailureCategory.COMMAND
     if ValidationError and isinstance(exc, ValidationError):
         return CollectorFailureCategory.VALIDATION
+    if isinstance(exc, AuthenticationError):
+        return CollectorFailureCategory.AUTH
 
     try:
         from django.db import Error as DjangoDBError

core/tests/test_errors.py

@@ -10,6 +10,7 @@
 from django.core.management.base import CommandError
 
 from core.errors import (
+    AuthenticationError,
     CollectorFailureCategory,
     _classify_os_error,
     classify_failure,
@@ -58,6 +59,13 @@ def test_classify_command_error():
     assert classify_failure(CommandError("bad")) is CollectorFailureCategory.COMMAND
 
 
+def test_classify_authentication_error():
+    assert (
+        classify_failure(AuthenticationError("bad creds"))
+        is CollectorFailureCategory.AUTH
+    )
+
+
 def test_classify_django_db_error_unknown():
     from django.db import OperationalError