Add new launch variable substitution called activeHost

[jeanbenitezu]

This PR introduces a new variable substitution, ${activeHost}, that allows users to dynamically reference the currently configured remote host in their debug configurations.

In addition, I added a small documentation about this variable substitution functionality, which may help others identify their goal.

🚀 Why

• Enables more flexible debug configurations that can adapt to different remote hosts
• Reduces the need to manually update host references across multiple configuration files

[TwitchBronBron]

This looks great! I'm good with the change, I just have one suggestion: What if we call the property activeHost instead? It feels like it pairs nicely with host, and feels like it slightly more clearly implies that "if there isn't an active host, set one and then use it"

In the future we're going to be introducing the concept of activeDevice in the UI where you can pick the device from a panel in the editor, set rules and toggles, etc. Which will replace the current brightscript.remoteControl.host setting and the remoteHost workspace state value.

What do you think?

[jeanbenitezu]

Hey Bron!

Thanks so much for taking the time to review this. I really appreciate it.

I was actually on the fence about the variable name, so activeHost sounds perfect, much cleaner and more intuitive 😅 I’ll make that change and push it shortly.

Also, the upcoming device picker feature sounds awesome!! looking forward to seeing it in action!

Happy Friday!