Stale dependency diagnostic does not show up under 'Messages' after opening VS Code

Description

Typically, when opening a file with a stale dependency, there is a diagnostic under 'Messages' that informs us that 'Restart File' needs to be called. However, right after VS Code is opened and the extension launches for the first time, that diagnostic only appears in the editor and under 'All Messages' after unfolding the section, not in 'Messages'. It would be nice if this was fixed so the error is always visible in the InfoView.

Additional Information

I suspect that this is due to a race condition caused by how the InfoView is informed about new diagnostics; when the stale dependency diagnostic is received, the InfoView probably isn't listening for these diagnostics yet.

Impact

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Start by reproducing the issue in VS Code: open a file with a stale dependency immediately after launching the extension and inspect the InfoView diagnostic handling. Trace how diagnostics reach the Messages and All Messages sections; done means the stale-dependency diagnostic is visible under Messages on first launch as well as in the editor.