Add go-e wallbox charger to live and statistics views

- PowerPoint/EnergyBar: add charger/charge fields
- getPower: query charger_10m/charger_1h alongside PV and meters
- getBars: compute daily charge kWh via LAG on charger_daily.eto_wh
- EnergyView: green Charger series in live power chart
- StatisticsView: purple Charge bars in statistics chart

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/api/client.ts

@@ -28,6 +28,7 @@ export interface EnergyBar {
   sell: number
   produce: number
   consume: number
+  charge: number
 }
 
 export interface PowerPoint {
@@ -35,6 +36,7 @@ export interface PowerPoint {
   pv: number
   house: number
   barn: number
+  charger: number
 }
 
 export interface BatteryPoint {