audit: migrate enums to StrEnum

app/audit.py

@@ -4,7 +4,7 @@ from __future__ import annotations
 
 import json
 import time
-from enum import Enum
+from enum import StrEnum
 from typing import TYPE_CHECKING, Any
 
 from flask import current_app, g
@@ -15,7 +15,7 @@ if TYPE_CHECKING:
     from sqlite3 import Row
 
 
-class AuditEvent(str, Enum):
+class AuditEvent(StrEnum):
     """Security-relevant event types for audit logging."""
 
     PASTE_CREATE = "paste_create"
@@ -33,7 +33,7 @@ class AuditEvent(str, Enum):
     URL_DELETE = "url_delete"
 
 
-class AuditOutcome(str, Enum):
+class AuditOutcome(StrEnum):
     """Outcome types for audit events."""
 
     SUCCESS = "success"