[Feature] Subscription mode missing.

### Search before asking

- [X] I searched in the [issues](https://github.com/apache/pulsar-client-cpp/issues) and found nothing similar.

### Version

There seams to be no way to set the subscription mode ?
https://pulsar.apache.org/docs/2.7.0/concepts-messaging/#what-is-a-subscription-mode

### Minimal reproduce step

There seams to be no way to set the subscription mode ?
https://pulsar.apache.org/docs/2.7.0/concepts-messaging/#what-is-a-subscription-mode

### What did you expect to see?

I expected to se subscription mode in ConsumerConfiguration.

### What did you see instead?

Nothing

### Anything else?

_No response_

### Are you willing to submit a PR?

- [ ] I'm willing to submit a PR!

Start with ConsumerConfiguration and compare its available options with the subscription modes described in the linked Pulsar messaging documentation. Add a way to select the subscription mode and verify that the supported modes are represented in the consumer configuration.

Written by the indexing model from the issue text.