In remote thin-client mode the Electron client and the backend it connects to
are separate installs that drift independently. The status bar previously showed
only the client version, hiding skew (e.g. client 0.15.1 talking to backend
0.16.0 looked fine).
Add a pure resolveVersionBar() helper (unit-tested) that, gated on
connection.mode === 'remote', renders both 'client vX · backend vY' from the
desktop appVersion and StatusResponse.version, and flags skew. Local mode is
byte-identical to before. Wire it into the status-bar version item.
ed1e2533b7