chore: import upstream snapshot with attribution

dotnet/samples/Demos/StructuredDataPlugin/ApplicationDbContext.cs

@@ -0,0 +1,51 @@
+// Copyright (c) Microsoft. All rights reserved.
+
+using System.Data.Entity;
+using Microsoft.Extensions.Configuration;
+
+namespace StructuredDataPlugin;
+
+/// <summary>
+/// Represents a database context for the structured data plugin demo.
+/// Inherits from Entity Framework's DbContext to provide database access and management.
+/// </summary>
+internal sealed class ApplicationDbContext : DbContext
+{
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ApplicationDbContext"/> class using configuration settings.
+    /// </summary>
+    /// <param name="config">The configuration object containing connection string information.</param>
+    /// <remarks>
+    /// The connection string is retrieved from the configuration using the pattern "ConnectionStrings:ApplicationDbContext".
+    /// </remarks>
+    public ApplicationDbContext(IConfiguration config) :
+        base(config[$"ConnectionStrings:{nameof(ApplicationDbContext)}"]!)
+    {
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="ApplicationDbContext"/> class using a direct connection string.
+    /// </summary>
+    /// <param name="connectionString">The connection string to the database.</param>
+    public ApplicationDbContext(string connectionString)
+        : base(connectionString)
+    {
+    }
+
+    /// <summary>
+    /// Configures the database model and its relationships.
+    /// </summary>
+    /// <param name="modelBuilder">The builder being used to construct the model for this context.</param>
+    /// <remarks>
+    /// This method:
+    /// - Disables database initialization
+    /// - Maps the Product entity to the "Products" table
+    /// - Calls the base configuration
+    /// </remarks>
+    protected override void OnModelCreating(DbModelBuilder modelBuilder)
+    {
+        Database.SetInitializer<ApplicationDbContext>(null);
+        modelBuilder.Entity<Product>().ToTable("Products");
+        base.OnModelCreating(modelBuilder);
+    }
+}