feat: add oscillator pane support with lightweight-charts v5

- Upgrade CDN from v4.1.0 to v5.1.0
- Add displayMode property to indicators ('overlay' vs 'pane')
- Mark oscillators (RSI, MACD, Stoch, ATR) as pane-type indicators
- Rewrite drawIndicatorsOnChart() to render oscillators in separate draggable panes
- Update all chart.addSeries() calls to v5 API with paneIndex parameter
- Add pane layout configuration with resizable separators

src/api/dashboard/static/js/indicators/bb.js

@@ -36,7 +36,8 @@ export class BollingerBandsIndicator extends BaseIndicator {
                 { id: 'upper', color: '#4caf50', title: 'Upper' },
                 { id: 'middle', color: '#4caf50', title: 'Middle', lineStyle: 2 },
                 { id: 'lower', color: '#4caf50', title: 'Lower' }
-            ]
+            ],
+            displayMode: 'overlay'
         };
     }
 }