Add OpenCost support for AKS Tools

OpenCost is a CNCF project for monitoring the cost of cloud-deployed Kubernetes clusters. It would be useful to be able to right-click an AKS cluster to deploy OpenCost into it and provide links to the UI. There is a bit of [Azure pricing integration](https://www.opencost.io/docs/configuration/azure-prices) that could be automated and the OpenCost installation is fairly lightweight (Prometheus + deployment of 2 containers). We could add API calls if that seems useful (ie. "node/namespace/pod/etc. cost for a fixed date (1d/3d/7d/etc.)). If this sounds interesting/useful I'm more than happy to assist from the OpenCost side.

I think this makes sense on the OSS side.

I did a plugin for Backstage, embedding the UI is also an option.

Start with the AKS cluster right-click entry point and the linked OpenCost Azure pricing documentation; no repository file or test is identified in the issue. First clarify whether the scope includes deployment, UI links, Azure pricing automation, and cost APIs, then define completion around the agreed scope.

Written by the indexing model from the issue text.