scaffold-archipy-decoratorlisted

# Scaffold ArchiPy Decorator ## Scope **Only** `helpers/decorators/`. Do not create utils or interceptors here. ## Before writing files 1. Inspect existing decorators, call sites, and the installed ArchiPy version for a matching decorator. 2. Infer sync/async style and project naming from the target call site. 3. Ask only for unresolved behavior. Prefer an ArchiPy decorator whenever it fits. 4. Preserve existing decorator modules; do not overwrite. ## Prefer ArchiPy Examples: - `from archipy.helpers.decorators.cache import ttl_cache_decorator` - `from archipy.helpers.decorators.sqlalchemy_atomic import postgres_sqlalchemy_atomic_decorator` - `from archipy.helpers.decorators.sqlalchemy_atomic import async_postgres_sqlalchemy_atomic_decorator` - `trace_span` / `trace_root` (+ async twins) from `archipy.helpers.decorators.tracing` - `measure_duration` / `count_calls` (+ async twins) from `archipy.helpers.decorators.metrics` - `timeout_decorator`, `retry_decorator`, `singleton_decorator`, `timing_decorator`, and `grpc_rate_limit_decorator` under `archipy.helpers.decorators` Show correct usage on a sample function; do not reimplement. UoW decorators belong on **logics**, not services/repositories. ## Custom decorator Create `helpers/decorators/<name>.py`: ```python from __future__ import annotations import functools import logging import time from collections.abc import Callable from typing import ParamSpec, TypeVar logger = logging.getLogger(__name__) P = ParamSpe