feat(core): add internal crypto isin resolution and subtitle mapping

FinlyticTechnicalAnalysis/Services/TechnicalAnalysisDbService.cs

@@ -125,7 +125,7 @@ public class TechnicalAnalysisDbService : ITechnicalAnalysisDbService
         var macroTask = FetchMacroDataAsync(cancellationToken);
         
         string? ticker = requestedTicker;
-        if (string.IsNullOrWhiteSpace(ticker))
+        if (string.IsNullOrWhiteSpace(ticker) || string.Equals(ticker.Trim(), cleanIsin, StringComparison.OrdinalIgnoreCase))
         {
             ticker = await _yahooScraper.ResolveTickerFromIsinAsync(cleanIsin, cancellationToken);
         }
@@ -326,7 +326,9 @@ public class TechnicalAnalysisDbService : ITechnicalAnalysisDbService
 
             if (cached != null && DateTime.UtcNow - cached.CalculatedAt < DbCacheTtl)
             {
-                if (!string.IsNullOrWhiteSpace(requestedTicker) && !string.Equals(cached.Ticker, requestedTicker, StringComparison.OrdinalIgnoreCase))
+                if (!string.IsNullOrWhiteSpace(requestedTicker) &&
+                    !string.Equals(requestedTicker.Trim(), cleanIsin, StringComparison.OrdinalIgnoreCase) &&
+                    !string.Equals(cached.Ticker, requestedTicker, StringComparison.OrdinalIgnoreCase))
                 {
                     return null; // Ticker mismatch, force refresh required
                 }

FinlyticTechnicalAnalysis/Services/YahooMarketDataScraper.cs

@@ -40,16 +40,21 @@ public interface IYahooMarketDataScraper
 public class YahooMarketDataScraper : IYahooMarketDataScraper
 {
     private readonly YahooFinanceClient _yahooClient;
+    private readonly Microsoft.Extensions.Configuration.IConfiguration _configuration;
     private readonly ILogger<YahooMarketDataScraper> _logger;
 
-    public YahooMarketDataScraper(YahooFinanceClient yahooClient, ILogger<YahooMarketDataScraper> logger)
+    public YahooMarketDataScraper(
+        YahooFinanceClient yahooClient,
+        Microsoft.Extensions.Configuration.IConfiguration configuration,
+        ILogger<YahooMarketDataScraper> logger)
     {
         _yahooClient = yahooClient;
+        _configuration = configuration;
         _logger = logger;
     }
 
     /// <summary>
-    /// Resolves ticker from ISIN using Yahoo Search API.
+    /// Resolves ticker from ISIN using Yahoo Search API or Crypto Subtitle resolution for internal ISINs.
     /// </summary>
     public async Task<string?> ResolveTickerFromIsinAsync(string isin, CancellationToken cancellationToken = default)
     {
@@ -61,6 +66,34 @@ public class YahooMarketDataScraper : IYahooMarketDataScraper
             return cleanIsin;
         }
 
+        // Crypto / Trade Republic interne ISINs (beginnend mit 'X', z. B. XF000BTC0017)
+        if (cleanIsin.StartsWith("X", StringComparison.OrdinalIgnoreCase))
+        {
+            var (cryptoSubtitle, cryptoName) = await FinlyticCore.Utils.CryptoSubtitleResolver.ResolveCryptoInfoAsync(
+                cleanIsin, _configuration.GetConnectionString("DefaultConnection"), cancellationToken);
+
+            if (!string.IsNullOrWhiteSpace(cryptoSubtitle))
+            {
+                var candidates = new[] { $"{cryptoSubtitle}-EUR", $"{cryptoSubtitle}-USD", cryptoSubtitle };
+                foreach (var candidate in candidates)
+                {
+                    try
+                    {
+                        var res = await FetchHistoricalCandlesWithCurrencyAsync(candidate, "5d", "1d", cancellationToken);
+                        if (res.Candles.Count > 0)
+                        {
+                            _logger.LogInformation("[{Channel}] Resolved Crypto ISIN {Isin} to {Symbol} using Subtitle {Sub}",
+                                "TechnicalAnalysisChannel", cleanIsin, candidate, cryptoSubtitle);
+                            return candidate;
+                        }
+                    }
+                    catch { }
+                }
+
+                return $"{cryptoSubtitle}-EUR";
+            }
+        }
+
         try
         {
             var searchResult = await _yahooClient.SearchAsync(cleanIsin, quotesCount: 10, newsCount: 0, cancellationToken);