Phase 6 (Stufe 6): MongoDB vollstaendig entfernt

- Legacy-Form stillgelegt: frm_main(.Designer/.resx) + frm_analytics(.Designer/.resx)
  geloescht, 'Open Legacy'-Menue aus LauncherForm entfernt.
- Program.cs: IMongoDatabase-Registrierung + closed_trades-Cleanup weg;
  Trade-Nummerierung liest jetzt hoechste TradeId aus ICopyTradeLogRepository.
- StartupHydrationService: Mongo-/Bson-Fallback entfernt (Settings kommen aus
  dem Repo; fehlende Accounts erhalten Default-Settings).
- Alle Mongo*Repository (Core 4 + Modul 4) geloescht; DI-Zweige auf EF/MySQL
  reduziert (AddCorePersistence, CopyTradingModule).
- ConfigMigrator: Mongo-Pfad (Run/MigrateSettings) entfernt; nur noch
  RunFromJson + VerifyMySql (kein Mongo-Treiber mehr).
- Modelle: [BsonId] entfernt (EF-Keys via HasKey); ObjectId-Defaults -> Guid.
- LiteDB-Shim (MongoDbLiteDBShim) geloescht; MongoDB.Driver- + LiteDB-Pakete
  aus App/Core entfernt; stale usings + user-sichtbare Strings bereinigt.
- DatabaseOptions/appsettings.json: Mongo-Provider/Connection-Felder entfernt.
- Build gruen; --verify-mysql bestaetigt 3 Accounts/3 Settings/32 Trader/2344 Markets.

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

services/StartupHydrationService.cs

@@ -3,8 +3,6 @@ using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Hosting;
-using MongoDB.Bson;
-using MongoDB.Driver;
 using PolyTrader.Core.Persistence;
 using PolyTrader.Modules.CopyTrading.Persistence;
 using PolyTraderSharp.Models;
@@ -26,7 +24,6 @@ namespace PolyTraderSharp.Services
         private readonly IPositionRepository _positionRepo;
         private readonly ICopyTradingAccountSettingsRepository _accountSettingsRepo;
         private readonly ITrackedTraderRepository _traderRepo;
-        private readonly IMongoDatabase _db;
         private readonly TerminalLogger _logger;
 
         public StartupHydrationService(
@@ -36,7 +33,6 @@ namespace PolyTraderSharp.Services
             IPositionRepository positionRepo,
             ICopyTradingAccountSettingsRepository accountSettingsRepo,
             ITrackedTraderRepository traderRepo,
-            IMongoDatabase db,
             TerminalLogger logger)
         {
             _state = state;
@@ -45,7 +41,6 @@ namespace PolyTraderSharp.Services
             _positionRepo = positionRepo;
             _accountSettingsRepo = accountSettingsRepo;
             _traderRepo = traderRepo;
-            _db = db;
             _logger = logger;
         }
 
@@ -85,14 +80,12 @@ namespace PolyTraderSharp.Services
 
         /// <summary>
         /// Lädt die Copytrading-Account-Settings in den State. Existiert für einen Account noch
-        /// kein Eintrag, werden die Werte einmalig aus den alten AccountState-Feldern des
-        /// Roh-Dokuments migriert (damit konfigurierte Limits nach dem Modell-Split erhalten bleiben).
+        /// kein Eintrag, wird ein Default-Eintrag angelegt und persistiert.
         /// </summary>
         private void HydrateAccountSettings(List<AccountState> accounts)
         {
             var existing = _accountSettingsRepo.GetAll().ToDictionary(s => s.AccountId);
-            var rawAccounts = _db.GetCollection<BsonDocument>("accounts");
-            int migrated = 0;
+            int created = 0;
 
             foreach (var acc in accounts)
             {
@@ -103,41 +96,13 @@ namespace PolyTraderSharp.Services
                 }
 
                 var settings = new CopyTradingAccountSettings { AccountId = acc.AccountId };
-                try
-                {
-                    var raw = rawAccounts.Find(Builders<BsonDocument>.Filter.Eq("_id", acc.AccountId)).FirstOrDefault();
-                    if (raw != null)
-                    {
-                        settings.PerMarketLimit = Dec(raw, "PerMarketLimit", settings.PerMarketLimit);
-                        settings.MaxPriceDifference = Dec(raw, "MaxPriceDifference", settings.MaxPriceDifference);
-                        settings.MaxBuyPrice = Dec(raw, "MaxBuyPrice", settings.MaxBuyPrice);
-                        settings.ProfitTarget = Dec(raw, "ProfitTarget", settings.ProfitTarget);
-                        settings.PreRedeemLimit = Dec(raw, "PreRedeemLimit", settings.PreRedeemLimit);
-                        settings.PerMasterLimit = Dec(raw, "PerMasterLimit", settings.PerMasterLimit);
-                        settings.perMaxTime6h = Dec(raw, "perMaxTime6h", settings.perMaxTime6h);
-                        settings.perMaxTime24h = Dec(raw, "perMaxTime24h", settings.perMaxTime24h);
-                        settings.perMaxTime72h = Dec(raw, "perMaxTime72h", settings.perMaxTime72h);
-                        settings.perMaxTimeNone = Dec(raw, "perMaxTimeNone", settings.perMaxTimeNone);
-                        migrated++;
-                    }
-                }
-                catch { }
-
                 _accountSettingsRepo.Upsert(settings);
                 _copyState.AccountSettings[acc.AccountId] = settings;
+                created++;
             }
 
-            if (migrated > 0)
-                _logger.Info($"Copytrading-Account-Settings: {migrated} Account(s) aus Alt-Feldern migriert.");
-        }
-
-        private static decimal Dec(BsonDocument doc, string field, decimal fallback)
-        {
-            if (doc.TryGetValue(field, out var v))
-            {
-                try { return v.ToDecimal(); } catch { }
-            }
-            return fallback;
+            if (created > 0)
+                _logger.Info($"Copytrading-Account-Settings: {created} Default-Eintrag/-Einträge angelegt.");
         }
 
         public Task StopAsync(CancellationToken cancellationToken) => Task.CompletedTask;