Workspace edits from `ruff server` commands occasionally fail in VS Code when operating on an yet-to-be-created file

[snowsignal]

Steps to reproduce:

1. Disable VS Code auto-save.
2. Add ALL to the select setting in the extension
3. Create a new .py file, but don't save it yet.
4. Add this code to the file:

import foo

def bar():
    unused = 4

5. Using the command palette (Ctrl/Cmd+Shift+P), repeatedly run ruff.applyAutofix.
6. The second time you run applyAutofix, you should see an error about a workspace edit that couldn't be applied.