support proxy grained istioctl experimental wait

[hzxuzhonghu]

(This is used to request new product features, please visit https://discuss.istio.io for questions on using Istio)

Describe the feature request Now istioctl experimental wait support checks whether a config like vs has been distributed to all proxies.

But in some case, we mind whether it has been distributed to a specific proxy, this especially makes sense as ambient introduced a new ztunnel type, which does not even watch traditional xds(lds rds CDs eds).

Describe alternatives you've considered

Affected product area (please put an X in all that apply)

[ ] Ambient [ ] Docs [ ] Dual Stack [ ] Installation [ ] Networking [ ] Performance and Scalability [ ] Extensions and Telemetry [ ] Security [ ] Test and Release [ ] User Experience [ ] Developer Infrastructure

Affected features (please put an X in all that apply)

[ ] Multi Cluster [ ] Virtual Machine [ ] Multi Control Plane

Additional context

[leosarra]

Hello @hzxuzhonghu , if that is fine for you I would like to work on a PR for this

[hzxuzhonghu]

Thanks for taking it