[Feature] Network Watcher Add-On Support

**Is your feature request related to a problem? Please describe.**

I want a supported way to use Network Watcher Tools with my AKS cluster.

The [Network Watcher extension](https://learn.microsoft.com/en-us/azure/virtual-machines/extensions/network-watcher-linux) can easily be installed onto a VM Scale Set. And an AKS Node Pool is a VM Scale Set.

I can manually install the Network Watcher extension on the VM Scale Set backing the Node Pool in my AKS cluster, and it works fine. It allows me to use Network Watcher tooling like Connection Monitor (so I can monitor my connection to CosmosDB, Redis, etc).

But I can't install the extension in a ***supported way*** for AKS Node Pools.

I logged a ticket with Azure support, and they said installing the Network Watcher Extension is "not supported" on AKS Node Pools and I should log a feature request here.

**Describe the solution you'd like**

I would like the Network Watcher extension to be considered an "add-on" like [the other various add-ons for AKS](https://learn.microsoft.com/en-us/azure/aks/integrations). Or have it as a configuration option that can be enabled on a Node Pool.

Enabling the add-on would install the Network Watcher extension in the VM Scale-Set backing the Node Pool.

That way we can start using Connection Monitor to monitor connections from our AKS clusters.

**Describe alternatives you've considered**

The support agent showed me the Network Observability add-on for AKS, but this is just Prometheus and Grafana.

It doesn't give me the features that Network Watcher has (like Connection Monitor).

**Additional context**

It's worth mentioning again that installing the Network Watcher extension on the VM Scale-Set backing an AKS Node Pool works perfectly fine.

There is just no **_supported_** integration between Network Watcher and AKS at the moment.