updated error handling

Author: bachuv

client/src/main/java/com/microsoft/durabletask/DurableTaskGrpcClient.java

@@ -371,7 +371,15 @@ public void rewindInstance(String instanceId, @Nullable String reason) {
         if (reason != null) {
             rewindRequestBuilder.setReason(StringValue.of(reason));
         }
-        this.sidecarClient.rewindInstance(rewindRequestBuilder.build());
+        try {
+            this.sidecarClient.rewindInstance(rewindRequestBuilder.build());
+        } catch (StatusRuntimeException e) {
+            if (e.getStatus().getCode() == Status.Code.FAILED_PRECONDITION) {
+                throw new IllegalStateException(
+                        "Orchestration instance '" + instanceId + "' is not in a failed state and cannot be rewound.", e);
+            }
+            throw e;
+        }
     }
 
     @Override

endtoendtests/src/main/java/com/functions/RewindTest.java

@@ -14,7 +14,6 @@
 import com.microsoft.durabletask.azurefunctions.DurableClientContext;
 import com.microsoft.durabletask.azurefunctions.DurableClientInput;
 import com.microsoft.durabletask.azurefunctions.DurableOrchestrationTrigger;
-import io.grpc.StatusRuntimeException;
 
 import java.time.Duration;
 import java.util.Optional;
@@ -106,7 +105,7 @@ public HttpResponseMessage startRewindNonFailedOrchestration(
         try {
             client.rewindInstance(instanceId, "Testing rewind on non-failed orchestration");
             context.getLogger().info("Rewind request sent for non-failed instance: " + instanceId);
-        } catch (StatusRuntimeException e) {
+        } catch (IllegalStateException e) {
             context.getLogger().info("Rewind on non-failed instance was rejected (expected): " + e.getMessage());
         }