Wrap gRPC StatusRuntimeException across all client and worker gRPC calls

[bachuv]

Summary

Most gRPC calls in the Java SDK let raw io.grpc.StatusRuntimeException escape to callers. The .NET SDK wraps RpcException (at minimum StatusCode.Cancelled → OperationCanceledException) for all entity client methods. The Java SDK should provide consistent domain-level exception wrapping so callers don't need to depend on gRPC types.

Current Behavior

The majority of gRPC methods across DurableTaskGrpcClient, GrpcDurableEntityClient, and DurableTaskGrpcWorker let StatusRuntimeException propagate unwrapped:

DurableTaskGrpcClient — no wrapping:

• suspendInstance()
• resumeInstance()
• terminate()
• raiseEvent()
• createInstanceWithRaise()
• getInstanceMetadata()

DurableTaskGrpcClient — wraps specific codes only:

• waitForInstanceStart() — DEADLINE_EXCEEDED → TimeoutException
• waitForInstanceCompletion() — DEADLINE_EXCEEDED → TimeoutException
• purgeInstances() — DEADLINE_EXCEEDED → TimeoutException
• rewindInstance() — NOT_FOUND → IllegalArgumentException, FAILED_PRECONDITION → IllegalStateException

GrpcDurableEntityClient — no wrapping:

• signalEntity()
• getEntityMetadata()
• queryEntities()
• cleanEntityStorage()

DurableTaskGrpcWorker — no wrapping:

• completeActivityTask()
• completeOrchestratorTask()
• completeEntityTask()

Expected Behavior

gRPC transport exceptions should be translated into SDK-level exceptions. At minimum:

• CANCELLED → CancellationException (closest Java equivalent to .NET's OperationCanceledException)
• NOT_FOUND → IllegalArgumentException or a dedicated not-found exception
• DEADLINE_EXCEEDED → TimeoutException (already done for some methods)

.NET SDK Reference

The .NET GrpcDurableEntityClient wraps RpcException for every entity method:

catch (RpcException e) when (e.StatusCode == StatusCode.Cancelled)
{
    throw new OperationCanceledException(
        $"The {nameof(this.SignalEntityAsync)} operation was canceled.", e, cancellation);
}