Feat(holidays): Implement database-backed holiday detection system

- Adds a new `MercadosFeriados` table to the database to persist market holidays.
- Implements `HolidayDataFetcher` to update holidays weekly from Finnhub API.
- Implements `IHolidayService` with in-memory caching to check for holidays efficiently.
- Worker service now skips fetcher execution on market holidays.
- Adds a new API endpoint `/api/mercados/es-feriado/{mercado}`.
- Integrates a non-blocking holiday alert into the `BolsaLocalWidget`."

src/Mercados.Worker/Program.cs

@@ -31,6 +31,13 @@ IHost host = Host.CreateDefaultBuilder(args)
         services.AddHttpClient("BcrDataFetcher").AddPolicyHandler(GetRetryPolicy());
         services.AddHttpClient("FinnhubDataFetcher").AddPolicyHandler(GetRetryPolicy());
 
+        // Servicio de caché en memoria de .NET
+        services.AddMemoryCache();
+        // Registramos nuestro nuevo servicio de feriados
+        services.AddScoped<IHolidayService, FinnhubHolidayService>();
+        services.AddScoped<IDataFetcher, HolidayDataFetcher>();
+        services.AddScoped<IMercadoFeriadoRepository, MercadoFeriadoRepository>();
+
         services.AddHostedService<DataFetchingService>();
     })
     .Build();