chore(api): align Python support with 3.12 (#34419)

Co-authored-by: Asuka Minato <i@asukaminato.eu.org>

api/context/execution_context.py

@@ -10,7 +10,7 @@ import threading
 from abc import ABC, abstractmethod
 from collections.abc import Callable, Generator
 from contextlib import AbstractContextManager, contextmanager
-from typing import Any, Protocol, TypeVar, final, runtime_checkable
+from typing import Any, Protocol, final, runtime_checkable
 
 from pydantic import BaseModel
 
@@ -188,8 +188,6 @@ class ExecutionContextBuilder:
 _capturer: Callable[[], IExecutionContext] | None = None
 _tenant_context_providers: dict[tuple[str, str], Callable[[], BaseModel]] = {}
 
-T = TypeVar("T", bound=BaseModel)
-
 
 class ContextProviderNotFoundError(KeyError):
     """Raised when a tenant-scoped context provider is missing."""