feat(settings): add Relays section showing active and recently connected relays

- Add relayStatusService to track relay connections with 20-minute history
- Add useRelayStatus hook for polling relay status updates
- Create RelaySettings component to display active and recent relays
- Update Settings and ThreePaneLayout to integrate relay status display
- Shows relay connection status with visual indicators and timestamps

src/components/ThreePaneLayout.tsx

@@ -97,6 +97,7 @@ const ThreePaneLayout: React.FC<ThreePaneLayoutProps> = (props) => {
               settings={props.settings}
               onSave={props.onSaveSettings}
               onClose={props.onCloseSettings}
+              relayPool={props.relayPool}
             />
           ) : (
             <ContentPanel