Support connecting the desktop app to a remote T3 Code backend

[Mitch515]

Problem

The desktop app currently assumes a local backend flow. That makes it harder to use the same T3 Code state across multiple machines or to point the desktop client at a backend that is already running elsewhere.

Proposal

Add a supported mode where the desktop app can connect to a remote T3 Code backend instead of always assuming a local one.

Why this would help

• lets a desktop client connect to an existing backend running on another machine
• improves continuity across laptop, desktop, phone, and web usage
• makes it easier to keep one shared session/state backend instead of treating each desktop app instance as isolated

Questions

• should remote backend support live behind an explicit opt-in desktop setting?
• what auth model would be expected for a remote desktop-to-backend connection?
• should the desktop app support switching between local and remote backends without restarting?

[Snowy7]

This feels closely related to #671.

My understanding is that #671 is framed around WSL first, but the architecture being discussed there looks broad enough that this could fit under the same umbrella.

The difference seems to be mostly level of abstraction:

• #671 talks about the backend-target architecture and how to model non-local runtimes cleanly
• #820 talks more directly about the user-facing outcome: letting the desktop app connect to an already running remote T3 Code backend

Because of that, I would probably treat #820 as a sub-problem or a slice of #671, rather than as a completely separate feature area.

So at minimum these should probably be cross-linked, I think it will help the maintainers track for remote backend support, #671 seems like the more natural so far.

I am pretty sure they mentioned once that remote is in their plans.

[clintebbesen]

Super keen for this, was searching for anything similar before posting myself.

My use case is wanting to be able to have T3 code running on a linux server in my server rack, and then connect to it from my laptop, phone, etc. This way I can have it working for me overnight without needing to keep mu computer on, or have it running while im driving to work, or use my phone to check in on how its going and give commands while im out and about. I have done this many times using CloudCLI UI https://github.com/siteboon/claudecodeui