Await coroutine functions in timer decorators

[FanWu-ai]

The timer decorator currently wraps coroutine functions with a synchronous function. It prints a duration as soon as the coroutine object is created, before the function body runs. It also makes inspect.iscoroutinefunction() return False for the decorated function.

Use an asynchronous wrapper for coroutine functions and await the original function inside the timed try/finally. Timing is reported when execution returns, raises, or is cancelled. Synchronous functions retain their existing wrapper.

Add five deterministic regression/control tests covering deferred execution, coroutine-function detection and metadata, return values and keyword arguments, exception identity, disabled output, and cancellation. Three tests fail against the unmodified implementation. The README includes a coroutine example.

Validation on Linux, CPython 3.12.14:

• Unmodified full unittest suite: 65 passed, no skips.
• Final full unittest suite: 70 passed, no skips.
• Project-pinned mypy 1.7.1: all five source files passed.
• Source distribution and wheel build: passed.
• git diff --check: passed.

The hosted Python/OS matrix has not been run locally.

Prepared with AI assistance.