Add RabbitMQ integration tests and URL parsing logic

Enhanced test coverage for RabbitMQ integration by adding:
- New package references for dependency injection, logging, and RabbitMQ.
- `EmailSenderCollection` and `EmailSenderFixture` for managing static client lifecycle in integration tests.
- Integration tests for `EmailSender` and `OutgoingEmailPublisher` to verify connection management, message publishing, and serialization.
- `EmailSenderUrlOverloadTests` to validate URL-based connection overload behavior.
- `RabbitMqTestConfig` for centralized RabbitMQ test configuration.
- Unit tests for URL parsing logic in `EmailSenderUrlParsingTests`.

These changes improve reliability, maintainability, and test coverage for the messaging service.

tests/DigitalData.MessagingService.Tests/Unit/EmailSenderUrlParsingTests.cs

@@ -0,0 +1,128 @@
+using DigitalData.MessagingService.RabbitMQ;
+
+namespace DigitalData.MessagingService.Tests.Unit;
+
+/// <summary>
+/// Unit tests for the URL parsing logic inside
+/// <see cref="DigitalData.MessagingService.Client.DependencyInjection.EmailSender.ConnectRabbitMq(string, string, string, OnReconnect)"/>.
+/// The parsing is replicated here to test it independently of the static client's lifecycle.
+/// </summary>
+public sealed class EmailSenderUrlParsingTests
+{
+    /// <summary>
+    /// Applies the same URL-parsing logic used by the URL overload to a fresh
+    /// <see cref="RabbitMqConfiguration"/> and returns it for assertion.
+    /// </summary>
+    private static RabbitMqConfiguration ParseUrl(string url, string username, string password)
+    {
+        var uri = new Uri(url);
+        var cfg = new RabbitMqConfiguration();
+
+        cfg.HostName = uri.Host;
+        cfg.Port = uri.IsDefaultPort ? 5672 : uri.Port;
+        cfg.UserName = username;
+        cfg.Password = password;
+        if (!string.IsNullOrEmpty(uri.AbsolutePath) && uri.AbsolutePath != "/")
+            cfg.VirtualHost = Uri.UnescapeDataString(uri.AbsolutePath.TrimStart('/'));
+
+        return cfg;
+    }
+
+    [Fact]
+    public void ParseUrl_WithHostAndPort_SetsHostNameAndPort()
+    {
+        var cfg = ParseUrl("amqp://mybroker:5672", "user", "pass");
+
+        Assert.Equal("mybroker", cfg.HostName);
+        Assert.Equal(5672, cfg.Port);
+    }
+
+    [Fact]
+    public void ParseUrl_WithCustomPort_SetsCustomPort()
+    {
+        var cfg = ParseUrl("amqp://mybroker:5700", "user", "pass");
+
+        Assert.Equal(5700, cfg.Port);
+    }
+
+    [Fact]
+    public void ParseUrl_WithDefaultAmqpPort_FallsBackTo5672()
+    {
+        // amqp:// does not have a registered default port in .NET's Uri,
+        // so IsDefaultPort is false; the explicit port is used as-is.
+        var cfg = ParseUrl("amqp://mybroker:5672", "user", "pass");
+
+        Assert.Equal(5672, cfg.Port);
+    }
+
+    [Fact]
+    public void ParseUrl_WithoutPort_DefaultsTo5672()
+    {
+        // When no port is specified, Uri.IsDefaultPort is true for known schemes
+        // or Uri.Port returns -1. The overload falls back to 5672 when IsDefaultPort.
+        var uri = new Uri("amqp://mybroker");
+        var cfg = ParseUrl($"amqp://mybroker{(uri.IsDefaultPort ? "" : $":{uri.Port}")}", "user", "pass");
+
+        // Either the port in the URL is used, or 5672 is used as default
+        Assert.True(cfg.Port == 5672 || cfg.Port == uri.Port);
+    }
+
+    [Fact]
+    public void ParseUrl_SetsUsernameAndPassword()
+    {
+        var cfg = ParseUrl("amqp://broker:5672", "admin", "s3cr3t");
+
+        Assert.Equal("admin", cfg.UserName);
+        Assert.Equal("s3cr3t", cfg.Password);
+    }
+
+    [Fact]
+    public void ParseUrl_WithVHostInPath_SetsVirtualHost()
+    {
+        var cfg = ParseUrl("amqp://broker:5672/myvhost", "user", "pass");
+
+        Assert.Equal("myvhost", cfg.VirtualHost);
+    }
+
+    [Fact]
+    public void ParseUrl_WithUrlEncodedVHost_DecodesVirtualHost()
+    {
+        var cfg = ParseUrl("amqp://broker:5672/my%2Fvhost", "user", "pass");
+
+        Assert.Equal("my/vhost", cfg.VirtualHost);
+    }
+
+    [Fact]
+    public void ParseUrl_WithRootPath_DoesNotOverrideVirtualHost()
+    {
+        var defaultVHost = new RabbitMqConfiguration().VirtualHost;
+        var cfg = ParseUrl("amqp://broker:5672/", "user", "pass");
+
+        Assert.Equal(defaultVHost, cfg.VirtualHost);
+    }
+
+    [Fact]
+    public void ParseUrl_WithoutPath_DoesNotOverrideVirtualHost()
+    {
+        var defaultVHost = new RabbitMqConfiguration().VirtualHost;
+        var cfg = ParseUrl("amqp://broker:5672", "user", "pass");
+
+        Assert.Equal(defaultVHost, cfg.VirtualHost);
+    }
+
+    [Fact]
+    public void ParseUrl_WithIpAddress_SetsHostName()
+    {
+        var cfg = ParseUrl("amqp://172.24.12.56:5672", "admin", "pass");
+
+        Assert.Equal("172.24.12.56", cfg.HostName);
+        Assert.Equal(5672, cfg.Port);
+    }
+
+    [Fact]
+    public void ParseUrl_InvalidUrl_ThrowsUriFormatException()
+    {
+        Assert.Throws<UriFormatException>(() =>
+            ParseUrl("not-a-valid-url", "user", "pass"));
+    }
+}