## Why
Registered Windows sandbox setup could appear complete even when Windows rejected the stored account passwords. Checking account flags alone did not detect these failures before runtime logon.
## What changed
- Check stored credentials for both offline and online accounts before reusing completed setup during non-refresh provisioning.
- Classify logon failure, expired-password, and password-change-required errors as `SandboxAccountCredentialMismatch`, preserving the underlying Windows error.
- Trigger full setup to rotate credentials only after verifying that recorded account SIDs still match. Propagate credential-file and policy errors without triggering password repair, and skip credential checks for refresh-only requests.
## Testing
Add tests for native error classification, missing credential files, healthy credentials, password failures on either account, policy failures, and rejection of repair when account ownership validation fails.
GitOrigin-RevId: b3aa02f82841dd2605b0c3585ec93144727721e6
zm-oai
17cd2834e3