Baseline: Ausgangszustand vor Modularisierung

Erster Commit des bestehenden monolithischen WinForms-Copytraders,
inklusive der Alt-Backups (*.bak), damit diese dauerhaft in der
Historie rekonstruierbar bleiben. Threema-Lib unter libs/ wurde
vendored (nested .git entfernt).

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

Models/CopySignal.cs

@@ -0,0 +1,19 @@
+namespace PolyTraderSharp.Models
+{
+    public class CopySignal
+    {
+        public int SourceTradeId { get; set; }
+        public int TraderId { get; set; }
+        public string MarketSlug { get; set; } = string.Empty;
+        public string ConditionId { get; set; } = string.Empty;
+        public string TokenId { get; set; } = string.Empty;
+        public string MarketQuestion { get; set; } = string.Empty;
+        public string Side { get; set; } = "BUY";
+        public decimal Price { get; set; }
+        public decimal Size { get; set; }
+        public string Outcome { get; set; } = string.Empty;
+        public DateTime Timestamp { get; set; }
+        public DateTime? EndDate { get; set; }
+        public string Reason { get; set; } = string.Empty;
+    }
+}