[Bug]: Mobile doesnt pick up model selection

### Platform

macOS

### Operating system version

macOS Tahoe 26.3.1 (a)

### System architecture

ARM64 (M1, M2, etc)

### PolyScope Version

0.14.0

### Bug description

When switching to mobile, the workspace's model selection isn't what I was using on my desktop. I think it goes back to the default.

### Steps to reproduce

- Open workspace.
- Pick a different model.
- Switch to mobile.
- See default model.

### Relevant log output

```shell

```

Start by reproducing the issue on macOS Tahoe 26.3.1 with PolyScope 0.14.0: select a non-default model in a workspace, then switch from desktop to mobile. Trace where the workspace model selection is read when mobile opens. Done means the selected model remains in use instead of reverting to the default.

Written by the indexing model from the issue text.