feat(auth): add configurable worker pool size for auto-refresh loop

- Introduced `auth-auto-refresh-workers` config option to override default concurrency.
- Updated `authAutoRefreshLoop` to support customizable worker counts.
- Enhanced token refresh scheduling flexibility by aligning worker pool with runtime configurations.

sdk/cliproxy/auth/conductor.go

@@ -2912,7 +2912,11 @@ func (m *Manager) StartAutoRefresh(parent context.Context, interval time.Duratio
 	}
 
 	ctx, cancelCtx := context.WithCancel(parent)
-	loop := newAuthAutoRefreshLoop(m, interval)
+	workers := refreshMaxConcurrency
+	if cfg, ok := m.runtimeConfig.Load().(*internalconfig.Config); ok && cfg != nil && cfg.AuthAutoRefreshWorkers > 0 {
+		workers = cfg.AuthAutoRefreshWorkers
+	}
+	loop := newAuthAutoRefreshLoop(m, interval, workers)
 
 	m.mu.Lock()
 	m.refreshCancel = cancelCtx