chore: add ast-grep rule to convert Optional[T] to T | None (#25560)

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

api/services/errors/base.py

@@ -1,6 +1,3 @@
-from typing import Optional
-
-
 class BaseServiceError(ValueError):
-    def __init__(self, description: Optional[str] = None):
+    def __init__(self, description: str | None = None):
         self.description = description

api/services/errors/llm.py

@@ -1,12 +1,9 @@
-from typing import Optional
-
-
 class InvokeError(Exception):
     """Base class for all LLM exceptions."""
 
-    description: Optional[str] = None
+    description: str | None = None
 
-    def __init__(self, description: Optional[str] = None):
+    def __init__(self, description: str | None = None):
         self.description = description
 
     def __str__(self):