Move EmbedInBinlog for EditorConfigFiles into _BeforeVBCSCoreCompile target and add test

Co-authored-by: jjonescz <3669664+jjonescz@users.noreply.github.com>

Author: Copilot

src/Compilers/Core/MSBuildTask/Microsoft.Managed.Core.targets

@@ -57,6 +57,13 @@
     <PropertyGroup Condition="'$(UseSharedCompilation)' == ''">
       <UseSharedCompilation>true</UseSharedCompilation>
     </PropertyGroup>
+
+    <!-- Embed EditorConfigFiles into the binary log. This is done here (rather than a static ItemGroup)
+         to ensure EditorConfigFiles added by analyzer packages in BeforeTargets="CoreCompile" targets
+         (e.g. NetAnalyzers, CodeStyle) are captured. -->
+    <ItemGroup>
+      <EmbedInBinlog Include="@(EditorConfigFiles)" />
+    </ItemGroup>
   </Target>
 
   <!--
@@ -145,7 +152,6 @@
     <GlobalAnalyzerConfigFiles Include="@(_AllDirectoriesAbove->'%(FullPath)'->Distinct()->Combine('.globalconfig'))" Condition="'$(DiscoverGlobalAnalyzerConfigFiles)' != 'false'" />
     <EditorConfigFiles Include="@(GlobalAnalyzerConfigFiles->Exists())" Condition="'$(DiscoverGlobalAnalyzerConfigFiles)' != 'false'" />
 
-    <EmbedInBinlog Include="@(EditorConfigFiles)" />
   </ItemGroup>
 
   <!--

src/Compilers/Core/MSBuildTaskTests/DotNetSdkTests.cs

@@ -654,5 +654,44 @@ public void TestGlobalConfigsCanBeManuallyAdded()
                     "mycustom.config"
                 }));
         }
+
+        [ConditionalFact(typeof(DotNetSdkAvailable), typeof(WindowsOnly), Reason = "https://github.com/dotnet/roslyn/issues/61017")]
+        public void TestEditorConfigFilesAddedByAnalyzerPackagesAreEmbeddedInBinlog()
+        {
+            // Simulate the behavior of analyzer packages (e.g., NetAnalyzers, CodeStyle) that add
+            // EditorConfigFiles in a target that runs BeforeTargets="CoreCompile". Verify those files
+            // are included in @(EmbedInBinlog) so they are captured in the binary log.
+            var srcFile = ProjectDir.CreateFile("lib1.cs").WriteAllText("class C { }");
+            var analyzerGlobalConfig = ProjectDir.CreateFile("analyzer.globalconfig").WriteAllText(@"is_global = true
+some_prop = some_val");
+
+            VerifyValues(
+                customProps: @"
+  <PropertyGroup>
+    <!-- Disable automatic global .editorconfig generation by the SDK -->
+    <GenerateMSBuildEditorConfigFile>false</GenerateMSBuildEditorConfigFile>
+  </PropertyGroup>",
+                customTargets: $@"
+  <!-- Simulate an analyzer package (e.g. NetAnalyzers) adding an EditorConfigFile
+       in a target that runs before CoreCompile. -->
+  <Target Name=""AddAnalyzerPackageEditorConfigFile"" BeforeTargets=""CoreCompile"">
+    <ItemGroup>
+      <EditorConfigFiles Include=""{analyzerGlobalConfig.Path}"" />
+    </ItemGroup>
+  </Target>",
+                targets: new[]
+                {
+                    "CoreCompile"
+                },
+                expressions: new[]
+                {
+                    "@(EmbedInBinlog)"
+                },
+                expectedResults: AppendExtraEditorConfigs(new[]
+                {
+                    Path.Combine(ProjectDir.Path, ".editorconfig"),
+                    analyzerGlobalConfig.Path
+                }));
+        }
     }
 }