fix(BA-2946): fix misleading SessionScopeAction docstring

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: fregataa

src/ai/backend/manager/services/session/base.py

@@ -24,12 +24,10 @@ def entity_type(cls) -> EntityType:
 
 @dataclass
 class SessionScopeAction(BaseScopeAction):
-    """Base class for session actions that operate within a scope (domain/project).
+    """Base class for session actions that operate within a scope.
 
     Used for operations like creating or searching sessions within a specific scope.
     Subclasses must implement scope_type(), scope_id(), and target_element() methods.
-
-    Note: Scope should typically be USER scope (user_id), not GLOBAL.
     """
 
     @override