Fix ReportingEndpoints URL validation causing CI test failure

src/SafeWebCore/Infrastructure/NetSecureHeadersOptionsValidator.cs

@@ -112,7 +112,11 @@ private static void ValidateReportingEndpoints(NetSecureHeadersOptions options,
             {
                 failures.Add($"{scope}: Reporting endpoint '{endpoint.Group}' URL must not be null, empty, or whitespace. Fix: provide an absolute HTTPS URL such as 'https://reports.example.com/csp'.");
             }
-            else if (!Uri.TryCreate(endpoint.Url, UriKind.Absolute, out _))
+            else if (!Uri.TryCreate(endpoint.Url, UriKind.Absolute, out var uri))
+            {
+                failures.Add($"{scope}: Reporting endpoint '{endpoint.Group}' URL must be absolute. Fix: use a full URL such as 'https://reports.example.com/csp'.");
+            }
+            else if (uri.Scheme != Uri.UriSchemeHttp && uri.Scheme != Uri.UriSchemeHttps)
             {
                 failures.Add($"{scope}: Reporting endpoint '{endpoint.Group}' URL must be absolute. Fix: use a full URL such as 'https://reports.example.com/csp'.");
             }

tests/SafeWebCore.Tests/NetSecureHeadersOptionsValidationTests.cs

@@ -103,6 +103,26 @@ public void StartWithRelativeReportingEndpointUrlThrowsOptionsValidationExceptio
         Assert.Contains("Fix: use a full URL such as 'https://reports.example.com/csp'", exception.Message);
     }
 
+    [Fact]
+    public void NonHttpSchemeReportingEndpointUrlThrowsOptionsValidationException()
+    {
+        // Arrange
+        var hostBuilder = CreateHostBuilder(opts =>
+        {
+            opts.ReportingEndpoints.Add(new()
+            {
+                Group = "default",
+                Url = "file:///reports"
+            });
+        });
+
+        // Act
+        var exception = Assert.Throws<OptionsValidationException>(() => hostBuilder.Start());
+
+        // Assert
+        Assert.Contains("Reporting endpoint 'default' URL must be absolute", exception.Message);
+    }
+
     [Fact]
     public void StartWithNelEnabledButEmptyNelValueThrowsOptionsValidationException()
     {