[Feature] Subscription-based Remote Control Service Integration (Stripe/Azure Web PubSub)

[estruyf]

Is your feature request related to a problem? Please describe.
Currently, remote control is achieved via a localhost service providing HTML and exposing the .demo folder as static content. With a shift toward Azure Web PubSub, this approach won't be feasible, so a new solution needs to be developed.

Describe the solution you'd like
Create a new subscription-based service with the following workflow:

• Users sign up and pay for a license via Stripe.
• Upon license purchase, users can request an API key.
• The API key enables connection from the VS Code extension to Azure Web PubSub.
• Remote users authenticate with their API key to connect to PubSub.
• Once connected, remotes request the full play information.
• VS Code responds with the data and remotes begin listening for updates.
• Two-way communication supports triggering previous/next scene commands.

Describe alternatives you've considered

• The current localhost service makes the .demo folder available statically, but this doesn't translate to the cloud/remote context. An alternative architecture or mechanism for remote slide/scene transitions is needed.

Additional context

• Open question: How will the remote get the next slide with Azure Web PubSub? Will a new backend API/service be needed to deliver .demo content?
• Payment integration: Stripe required for licensing.
• Secure distribution of API keys and PubSub channels should be considered.