feat: Implement ExistingDatabaseContext for managing existing databases with customizable naming strategies and auto-discovery of entities

feat: Add SqlServerSchemaProvider for extracting database schema information from SQL Server

feat: Introduce DatabaseType and NamingStrategy enums for better database management and naming conventions

feat: Create IDatabaseDiscovery and IDatabaseManager interfaces for database operations and metadata retrieval

feat: Develop REST service client architecture with BaseRestServiceClient and SAP Business One specific implementation

feat: Implement REST service discovery page with UI for connecting to SAP Business One Service Layer and displaying discovered entities

DataConnection/DB/Interfaces/IDatabaseSchemaProvider.cs

@@ -0,0 +1,17 @@
+using System.Collections.Generic;
+using System.Threading.Tasks;
+
+namespace DataConnection.Interfaces;
+
+/// <summary>
+/// Interfaccia per provider di estrazione dello schema del database
+/// </summary>
+public interface IDatabaseSchemaProvider
+{
+    /// <summary>
+    /// Estrae lo schema del database (tabelle e colonne)
+    /// </summary>
+    /// <param name="connectionString">Stringa di connessione al database</param>
+    /// <returns>Struttura gerarchica delle tabelle e delle loro colonne</returns>
+    Task<IDictionary<string, IEnumerable<DbColumnInfo>>> GetDatabaseSchemaAsync(string connectionString);
+}