Add OpenVINO AI Plugins to Snap

[frenchwr]

Important: @lucyllewy I PR'd this against the master branch but would propose creating a new track (openvino-ai-plugins) for this work that eventually can deploy to a dedicated channel for the snap. As the repo maintainer, this would require you to create the new branch and update the base branch in this PR.

Also note I included two commits from https://github.com/diddlesnaps/audacity/pull/41 and https://github.com/diddlesnaps/audacity/pull/42 , which may be applied to master as they address issues with the current snap from the Store from latest/candidate.

Summary

This PR enables five separate AI features in Audacity for users on Intel hardware. As mentioned above, I propose a new branch and snap track for this work because (i) the plugins are designed to function on Intel hardware only and (ii) the AI models 6.2 GiB in size and installed inside the snap, so only users who specifically request the plugins should receive the models.

Model installation

I've included a script for downloading the required models from Hugging Face. The script is designed to be run manually before building the snap. The model files are not under source control.

I considered other designs for installing the models (e.g. deploying an interactive script inside the snap to allow users to install models themselves) but ultimately chose to include the models (which, at 6.2 GiB total, are not enormous) inside the snap as the simplest approach for users who may not be so Linux savvy.

Coordination with the Store

• If you agree with the dedicated track, we will need to create a snap forum post for requesting the new track.
• We will also need to a separate forum post for requesting autoconnections for the new intel-npu and npu-libs plugs.

I realize this is a lot, and I don't want to assume you have an abundance of time or motivation to work on this, so please let me know how I might be able to help. In fact, I'd be happy to be added as a maintainer on the repo and/or as a collaborator for the snap in the store to help guide these steps.

I'd also be interested in helping to shepherd ownership to the snapcrafters team, as it seems from the README that most of the requirements are already done.