Sample Generation - ExampleValueExpressionBuilder and OperationSample parity with autorest generator

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Primitives/ScmKnownParameters.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT License.
 
 using System;
+using System.ClientModel;
 using System.ClientModel.Primitives;
 using System.Text.Json;
 using System.Threading;

packages/http-client-csharp/generator/Microsoft.TypeSpec.Generator.ClientModel/src/Providers/Samples/ExampleParameterValue.cs

@@ -0,0 +1,55 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+using Microsoft.TypeSpec.Generator.Expressions;
+using Microsoft.TypeSpec.Generator.Input;
+using Microsoft.TypeSpec.Generator.Primitives;
+
+namespace Microsoft.TypeSpec.Generator.ClientModel.Providers.Samples
+{
+    /// <summary>
+    /// Represents a parameter value in a sample. Supports two modes:
+    /// - <see cref="Value"/>: raw example data that will be converted to a C# expression later
+    /// - <see cref="Expression"/>: a pre-built C# expression (used for known parameters like credentials, endpoints)
+    /// </summary>
+    public class ExampleParameterValue
+    {
+        public ExampleParameterValue(string name, CSharpType type, InputExampleValue value)
+        {
+            Name = name;
+            Type = type;
+            Value = value;
+        }
+
+        public ExampleParameterValue(string name, CSharpType type, ValueExpression expression)
+        {
+            Name = name;
+            Type = type;
+            Expression = expression;
+        }
+
+        /// <summary>
+        /// The parameter name.
+        /// </summary>
+        public string Name { get; }
+
+        /// <summary>
+        /// The C# type of the parameter.
+        /// </summary>
+        public CSharpType Type { get; }
+
+        /// <summary>
+        /// Raw example data from the spec or mock builder. Will be converted to a
+        /// <see cref="ValueExpression"/> via <see cref="ExampleValueExpressionBuilder"/>.
+        /// Mutually exclusive with <see cref="Expression"/>.
+        /// </summary>
+        public InputExampleValue? Value { get; }
+
+        /// <summary>
+        /// A pre-built C# expression. Used for known parameters (credentials, endpoints)
+        /// where the expression is fixed regardless of example data.
+        /// Mutually exclusive with <see cref="Value"/>.
+        /// </summary>
+        public ValueExpression? Expression { get; }
+    }
+}