Fix WithBody to support multi-line request bodies

- Added RegexOptions.Singleline to StringExtensions.MatchesWildcard
- Added test for multi-line body matching with wildcard patterns
- All 107 tests pass

Co-authored-by: dennisdoomen <572734+dennisdoomen@users.noreply.github.com>

Author: Copilot

Mockly.Specs/HttpMockSpecs.cs

@@ -480,6 +480,36 @@ public async Task Can_match_body_against_a_wildcard_pattern()
             response.StatusCode.Should().Be(HttpStatusCode.NoContent);
         }
 
+        [Fact]
+        public async Task Can_match_multi_line_body_against_a_wildcard_pattern()
+        {
+            // Arrange
+            var mock = new HttpMock();
+
+            mock.ForPost()
+                .WithPath("/api/test")
+                .WithBody("*<entity>*<condition*value=\"0\"*")
+                .RespondsWithStatus(HttpStatusCode.NoContent);
+
+            var client = mock.GetClient();
+
+            // Act
+            var response = await client.PostAsync("https://localhost/api/test",
+                new StringContent(
+                    """
+                    <fetch>
+                      <entity>
+                        <filter>
+                          <condition attribute="statecode" operator="eq" value="0"/>
+                        </filter>
+                      </entity>
+                    </fetch>
+                    """));
+
+            // Assert
+            response.StatusCode.Should().Be(HttpStatusCode.NoContent);
+        }
+
         [Fact]
         public async Task Can_match_the_body_against_a_json_string_ignoring_layout()
         {

Mockly/Common/StringExtensions.cs

@@ -23,7 +23,7 @@ public static bool MatchesWildcard(this string text, string wildcardPattern)
             .Replace("\\*", ".*")
             .Replace("\\?", ".");
 
-        return Regex.IsMatch(text, regexPattern, RegexOptions.IgnoreCase);
+        return Regex.IsMatch(text, regexPattern, RegexOptions.IgnoreCase | RegexOptions.Singleline);
     }
 
     /// <summary>