fix(directory): cancel snapshot pulls from departed silos - #10318

src/Orleans.Runtime/GrainDirectory/GrainDirectoryPartition.cs:109

• This post-wait cancellation check only observes ShutdownToken. If the caller-provided cancellationToken is canceled after WaitForRange completes (but before snapshot construction), this method will continue building the snapshot unnecessarily. Since you already created a linked token, use that for the final ThrowIfCancellationRequested check.

        ShutdownToken.ThrowIfCancellationRequested();

src/Orleans.Runtime/GrainDirectory/GrainDirectoryPartition.cs:582

• This snapshot pull is no longer bound to the local partition ShutdownToken. Previously the call used WaitAsync(ShutdownToken), ensuring the range-lock acquisition path could abort promptly during local shutdown; now InvokeOnClusterMember waits solely on the remote member token and can block until the messaging timeout if this silo is stopping.

                var snapshot = await InvokeOnClusterMember(
                    previousOwner,
                    cancellationToken => partition.GetSnapshotAsync(
                        current.Version,
                        previousVersion,

src/Orleans.Runtime/GrainDirectory/DistributedGrainDirectory.cs:190

• InvokeAsync links the per-request token with GetClusterMemberCancellationToken(owner). If the token cache has not yet been updated for the selected owner (e.g., after a RefreshViewAsync returns a newer view but before ProcessMembershipUpdates calls _clusterMemberCancellationTokens.Update for that snapshot), GetToken returns a pre-canceled token and the call is immediately canceled/retried (and can fail after MaxAttempts). Consider lazily seeding/updating the token cache when the latest membership snapshot still considers the owner invokable.

                RequestContext.Set("gid", partitionReference.GetGrainId());
                using var requestCts = CancellationTokenSource.CreateLinkedTokenSource(
                    cancellationToken,
                    GetClusterMemberCancellationToken(owner));
                invokeResult = await func(partitionReference, view.Version, state, requestCts.Token);