[ 2024-08-21; Reflector poll ]

Set priority to 1 after reflector poll.

`promise()` can probably be Throws: Nothing (along with a bunch of other coroutine_handle members), but `resume()` certainly can throw. Also AS-EXCEPT-PTR can throw for the `error_code` case (that might be worth a separate issue though).

The specification of awaitable-receiver in [exec.as.awaitable]/p4 as of N4988 is not taking into consideration the fact that the resume() and promise() member functions on coroutine_handle<P> are not marked noexcept. awaitable-receiver's member functions must all be noexcept, but they are specified as being "equivalent to" statement that call resume() and promise() outside of try/catch blocks.