Bug report – Google Drive sync fails on Windows: EINVAL: invalid argument, mkdir 'G:' (v0.6.1)

Environment

App: Vowen v0.6.1
OS: Windows 11
Cloud provider: Google Drive (Google Drive for Desktop, streaming mode, mounted as drive G:)

Summary

Google Drive sync fails permanently. Vowen attempts to create its sync folder directly at the root of the mounted Google Drive virtual unit (G:) instead of using a subfolder inside "My Drive" (e.g., G:\My Drive\Vowen). On Windows, mkdir "G:" is an invalid operation, so the sync fails with EINVAL: invalid argument, mkdir 'G:' every time.

Steps to reproduce

On Windows 11, install Google Drive for Desktop (streaming mode, virtual drive mounted as G:).
In Vowen, connect Google Drive.
No option is offered to choose the sync folder or path — the app assumes the drive root.
Any sync trigger fails with: EINVAL: invalid argument, mkdir 'G:'

Observed behavior

The error fires on every sync trigger: boot, change, focus, blur, backstop, and even repair-boot (the app's own self-repair mechanism retries the same invalid path, so it never recovers). Sample from sync-log.jsonl:

{"at":"2026-10-23T12:32:14.624Z","reason":"boot","action":"error","error":"EINVAL: invalid argument, mkdir 'G:'"}

{"at":"2026-10-23T13:02:06.865Z","reason":"backstop","action":"error","error":"EINVAL: invalid argument, mkdir 'G:'"}

{"at":"2026-10-23T14:36:55.160Z","reason":"repair-boot","action":"error","error":"EINVAL: invalid argument, mkdir 'G:'"}

(Full sync-log.jsonl available on request.)

Additional findings (troubleshooting already done)

Disconnecting and reconnecting Google Drive does not help; no folder/path picker is shown during reconnection.
The path is not stored anywhere user-editable: it does not appear in settings.json, sync-meta.json, Preferences, or Local Storage/IndexedDB. It appears to be constructed at runtime.
Expected behavior: the sync target should be a subfolder such as G:\My Drive\Vowen, and ideally the user should be able to configure it in Settings.

Impact

Sync is completely non-functional for users whose Google Drive for Desktop is mounted as a drive letter. Since the root of the virtual drive is not a valid mkdir target on Windows, this affects every Windows user in this setup.