Extension API: Support for remote execution of apps

[Joannis]

Describe the solution you'd like
I'd like to select a target platform (e.g. Android, or a remote Linux device), and cross-compile my app for that platform with the appropriate SDK of my choosing (Linux can have multiple SDKs).

The extension API I call to make this happen can provide metadata like the target device and/or credentials (think of an SSH remote, an OCI registry, Android device ID, IP address, ...).

Once cross-compiled, my own VSCode extension can provide a command (or SwiftPM build tool) to package the artifact, then another one to upload it to the device and run it.

Ideally, if the platform supports remote debugging, the VSCode extension knows how to connect to that over GDB or LLDB's own protocol and sets up lldb/lldb-dap correctly using sane defaults. Alternatively, the third-party extension can provide these LLDB attach commands.

Describe alternatives you've considered
Currently we hand-roll all of this logic, but it would be nice to have an integrated solution that can be replicated uniformly for many different target platforms.

Additional context
Add any other context or screenshots about the feature request here.