fix(files): virtual files status can take minutes to load on Windows

[veryCrunchy]

Problem

Opening Virtual files on Windows can leave Storage on this device loading for about four minutes. The eventual status reports a timeout while checking the Cloud Files root for local metadata corruption.

Scope

Keep ordinary Windows startup recovery limited to resident filesystem entries. Keep the shared storage screen useful during slow checks and recoverable after a failed status request.

Acceptance criteria

• Ordinary startup does not recursively list unopened remote folders or ask Windows to populate them during local traversal.
• Existing local changes and explicit corruption recovery remain covered by regression tests.
• Slow checks explain their progress; failed refreshes retain the previous snapshot and offer a retry.
• Native Windows startup, desktop tests, shared Android compilation, and Windows packaging are validated. Other platform runtime validation is reported separately.

Priority: high. Area: Files and sync. Platforms: Windows and shared storage UI.