fix: TS type error in VPN status, remove unused assignment warning

- Fix vpnStatus type mismatch (provider: string|undefined vs string|null)
- Remove redundant history_dirty assignment in health_monitor.rs

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

core/archipelago/src/health_monitor.rs

@@ -539,7 +539,6 @@ pub fn spawn_health_monitor(state: Arc<StateManager>, data_dir: PathBuf) {
                                         other.name, container.name);
                                     tracker.clear(&other.name);
                                     restart_history.clear(&other.name);
-                                    history_dirty = true;
                                 }
                             }
                         }