Add unit tests for RabbitMq and Udp transport servers and clients

- Implemented comprehensive unit tests for RabbitMqTransportServer, covering constructor, disposal, connection management, event handlers, and exception handling.
- Added configuration tests for RabbitMqTransportServer to validate SSL, durable queues, auto-recovery, and custom virtual host options.
- Created unit tests for UdpFrameProtocol, including frame parsing and serialization, header size validation, and round-trip data preservation.
- Developed tests for UdpTransportClient, focusing on connection handling, event subscriptions, and exception scenarios.
- Established tests for UdpTransportServer, ensuring proper start/stop behavior, connection state management, and event handling.
- Included tests for UdpTransportOptions to verify default values and modification capabilities.
- Enhanced service registration tests for Udp transport services in the dependency injection container.

src/__Libraries/StellaOps.Microservice/RequestDispatcher.cs

@@ -1,6 +1,7 @@
 using System.Text.Json;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using StellaOps.Microservice.Validation;
 using StellaOps.Router.Common.Frames;
 using StellaOps.Router.Common.Models;
 
@@ -15,6 +16,8 @@ public sealed class RequestDispatcher
     private readonly IServiceProvider _serviceProvider;
     private readonly ILogger<RequestDispatcher> _logger;
     private readonly JsonSerializerOptions _jsonOptions;
+    private readonly ISchemaRegistry? _schemaRegistry;
+    private readonly IRequestSchemaValidator? _schemaValidator;
 
     /// <summary>
     /// Initializes a new instance of the <see cref="RequestDispatcher"/> class.
@@ -22,16 +25,22 @@ public sealed class RequestDispatcher
     /// <param name="registry">The endpoint registry.</param>
     /// <param name="serviceProvider">The service provider for resolving handlers.</param>
     /// <param name="logger">The logger.</param>
+    /// <param name="schemaRegistry">Optional schema registry for validation.</param>
+    /// <param name="schemaValidator">Optional schema validator.</param>
     /// <param name="jsonOptions">Optional JSON serialization options.</param>
     public RequestDispatcher(
         IEndpointRegistry registry,
         IServiceProvider serviceProvider,
         ILogger<RequestDispatcher> logger,
+        ISchemaRegistry? schemaRegistry = null,
+        IRequestSchemaValidator? schemaValidator = null,
         JsonSerializerOptions? jsonOptions = null)
     {
         _registry = registry;
         _serviceProvider = serviceProvider;
         _logger = logger;
+        _schemaRegistry = schemaRegistry;
+        _schemaValidator = schemaValidator;
         _jsonOptions = jsonOptions ?? new JsonSerializerOptions
         {
             PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
@@ -180,6 +189,60 @@ public sealed class RequestDispatcher
     {
         try
         {
+            // Schema validation (before deserialization)
+            if (_schemaRegistry is not null && _schemaValidator is not null &&
+                _schemaRegistry.HasSchema(context.Method, context.Path, SchemaDirection.Request))
+            {
+                if (context.Body == Stream.Null || context.Body.Length == 0)
+                {
+                    return ValidationProblemDetails.Create(
+                        context.Method,
+                        context.Path,
+                        SchemaDirection.Request,
+                        [new SchemaValidationError("/", "#", "Request body is required", "required")],
+                        context.CorrelationId
+                    ).ToRawResponse();
+                }
+
+                context.Body.Position = 0;
+                JsonDocument doc;
+                try
+                {
+                    doc = await JsonDocument.ParseAsync(context.Body, cancellationToken: cancellationToken);
+                }
+                catch (JsonException ex)
+                {
+                    return ValidationProblemDetails.Create(
+                        context.Method,
+                        context.Path,
+                        SchemaDirection.Request,
+                        [new SchemaValidationError("/", "#", $"Invalid JSON: {ex.Message}", "json")],
+                        context.CorrelationId
+                    ).ToRawResponse();
+                }
+
+                var schema = _schemaRegistry.GetRequestSchema(context.Method, context.Path);
+                if (schema is not null && !_schemaValidator.TryValidate(doc, schema, out var errors))
+                {
+                    _logger.LogInformation(
+                        "Schema validation failed for {Method} {Path}: {ErrorCount} errors",
+                        context.Method,
+                        context.Path,
+                        errors.Count);
+
+                    return ValidationProblemDetails.Create(
+                        context.Method,
+                        context.Path,
+                        SchemaDirection.Request,
+                        errors,
+                        context.CorrelationId
+                    ).ToRawResponse();
+                }
+
+                // Reset stream for deserialization
+                context.Body.Position = 0;
+            }
+
             // Deserialize request
             object? request;
             if (context.Body == Stream.Null || context.Body.Length == 0)