Initial commit: IBKRTrader

.NET WinForms-Anwendung (Core, Modules/CongressTrading, UI).
Enthaelt .gitignore und settings.example.json als Konfigurationsvorlage.
Echte settings.json mit Zugangsdaten ist bewusst ausgeschlossen.

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

Core/Budget/BudgetService.cs

@@ -0,0 +1,48 @@
+using IBKRTrader.Core.Database;
+using IBKRTrader.Core.Logging;
+
+namespace IBKRTrader.Core.Budget;
+
+/// <summary>
+/// Verwaltet das Budget pro Modul.
+/// Liest/schreibt core_budget.
+/// </summary>
+public class BudgetService
+{
+    private readonly DatabaseService _db;
+    private readonly LoggingService  _logger;
+
+    public BudgetService(DatabaseService db, LoggingService logger)
+    {
+        _db     = db;
+        _logger = logger;
+    }
+
+    public async Task<decimal> GetAvailableBudgetAsync(string module)
+    {
+        var row = await _db.QueryFirstOrDefaultAsync<dynamic>(
+            "SELECT total_budget, used_budget FROM `core_budget` WHERE module = @module",
+            new { module });
+
+        if (row == null) return 0;
+        return (decimal)row.total_budget - (decimal)row.used_budget;
+    }
+
+    public async Task ReserveBudgetAsync(string module, decimal amount)
+    {
+        await _db.ExecuteAsync(
+            @"INSERT INTO `core_budget` (module, used_budget)
+              VALUES (@module, @amount)
+              ON DUPLICATE KEY UPDATE used_budget = used_budget + @amount",
+            new { module, amount });
+    }
+
+    public async Task ReleaseBudgetAsync(string module, decimal amount)
+    {
+        await _db.ExecuteAsync(
+            @"UPDATE `core_budget`
+              SET used_budget = GREATEST(0, used_budget - @amount)
+              WHERE module = @module",
+            new { module, amount });
+    }
+}