fix: initial balance calculation and UI improvements

- Fix initial balance using available_balance instead of total_equity
- Fix WSMonitor nil pointer by starting market monitor before loading traders
- Add strategy name display on traders list and dashboard pages
- Various position sync and trading improvements

web/src/components/TraderConfigModal.tsx

@@ -368,7 +368,7 @@ export function TraderConfigModal({
                         selectedStrategy.config.coin_source.source_type === 'oi_top' ? 'OI Top' : '混合'}
                     </div>
                     <div>
-                      风控等级: {((selectedStrategy.config.risk_control?.max_position_ratio || 0.3) * 100).toFixed(0)}% 仓位
+                      保证金上限: {((selectedStrategy.config.risk_control?.max_margin_usage || 0.9) * 100).toFixed(0)}%
                     </div>
                   </div>
                 </div>