Expand description
Completion strategies (§5.10).
CompletionStrategy decides how the runtime detects that a stream
has finished its outstanding work. The F1 default is
HostFnCompletion, which uses cuLaunchHostFunc to schedule a
callback that wakes a Tokio waker — sub-microsecond latency, no
polling overhead, scales to many concurrent operations.
Two fallback strategies are present as stubs for F2: PolledCompletion
for environments that block host-functions, and SyncCompletion for
debugging / deterministic-replay testing.