@

R7: Dashboard-View + DashboardService (Abschluss Feinschliff)

- Core/Trading/DashboardService: aggregiert Positionen/Exposure/Trades via EF (DashboardSnapshot)
- UI/Views/DashboardView: Trading-Modus, aggregierte Kennzahlen, geladene Module (+ Aktivierungs-Status)
- core.dashboard-View registriert (Order 5) mit dashboard-Icon
- Tests: DashboardService (leer + Aggregation, InMemory) -> 58/58 gruen; smoke-ui deckt alle 5 Views ab

Kurskorrektur R1-R7 abgeschlossen: IBKRTrader folgt dem PolytraderSharp-Konzept.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
@

src/IBKRTrader.Core/Trading/DashboardService.cs

@@ -0,0 +1,26 @@
+using IBKRTrader.Core.Persistence.Ef;
+using Microsoft.EntityFrameworkCore;
+
+namespace IBKRTrader.Core.Trading;
+
+/// <summary>Aggregierte Kennzahlen über alle Module für das Dashboard.</summary>
+public sealed record DashboardSnapshot(int OpenPositions, decimal TotalExposure, int TotalTrades);
+
+/// <summary>Liest aggregierte Portfolio-Kennzahlen (EF Core) für die Dashboard-Ansicht.</summary>
+public sealed class DashboardService
+{
+    private readonly IDbContextFactory<CoreDbContext> _dbf;
+
+    public DashboardService(IDbContextFactory<CoreDbContext> dbf) => _dbf = dbf;
+
+    public async Task<DashboardSnapshot> GetSnapshotAsync(CancellationToken ct = default)
+    {
+        await using var db = await _dbf.CreateDbContextAsync(ct);
+        var positions = await db.Positions.ToListAsync(ct);
+        var trades    = await db.TradeHistory.CountAsync(ct);
+        return new DashboardSnapshot(
+            OpenPositions: positions.Count,
+            TotalExposure: positions.Sum(p => p.Quantity * p.AvgPrice),
+            TotalTrades:   trades);
+    }
+}