Apply editorconfig settings to moved ExternalAccess

.editorconfig

@@ -284,3 +284,20 @@ dotnet_diagnostic.IDE2006.severity = warning
 # CA1822: Make member static
 # There is a risk of accidentally breaking an internal API that partners rely on though IVT.
 dotnet_code_quality.CA1822.api_surface = private
+
+[**/{ExternalAccess}/**/*.{cs,vb}]
+
+# RS0016: Only enable if API files are present
+dotnet_public_api_analyzer.require_api_files = true
+
+dotnet_diagnostic.RS0051.severity = error
+dotnet_diagnostic.RS0052.severity = error
+dotnet_diagnostic.RS0053.severity = error
+dotnet_diagnostic.RS0054.severity = error
+dotnet_diagnostic.RS0055.severity = error
+dotnet_diagnostic.RS0056.severity = error
+dotnet_diagnostic.RS0057.severity = error
+dotnet_diagnostic.RS0058.severity = error
+dotnet_diagnostic.RS0059.severity = error
+dotnet_diagnostic.RS0060.severity = error
+dotnet_diagnostic.RS0061.severity = error

src/EditorFeatures/ExternalAccess/Copilot/.editorconfig

@@ -0,0 +1,3 @@
+[**]
+dotnet_public_api_analyzer.skip_namespaces = Microsoft.CodeAnalysis.ExternalAccess.Copilot.Internal
+

src/Features/ExternalAccess/AspNetCore/.editorconfig

@@ -0,0 +1,2 @@
+[**]
+dotnet_public_api_analyzer.skip_namespaces = Microsoft.CodeAnalysis.ExternalAccess.AspNetCore.Internal

src/Features/ExternalAccess/AspNetCore/EmbeddedLanguages/AspNetCoreCSharpRouteSyntaxDetector.cs

@@ -30,7 +30,8 @@ private AspNetCoreCSharpRouteSyntaxDetector()
     {
     }
 
-    public static bool IsEmbeddedLanguageToken(
+#pragma warning disable CA1822 // Mark members as static
+    public bool IsEmbeddedLanguageToken(
         SyntaxToken token,
         SemanticModel semanticModel,
         CancellationToken cancellationToken,
@@ -39,4 +40,5 @@ public static bool IsEmbeddedLanguageToken(
     {
         return s_detector.IsEmbeddedLanguageToken(token, semanticModel, cancellationToken, out identifier, out options);
     }
+#pragma warning restore CA1822
 }

src/Features/ExternalAccess/OmniSharp/.editorconfig

@@ -0,0 +1,2 @@
+[**]
+dotnet_public_api_analyzer.skip_namespaces = Microsoft.CodeAnalysis.ExternalAccess.OmniSharp.Internal

src/VisualStudio/ExternalAccess/Apex/.editorconfig

@@ -0,0 +1,4 @@
+[**]
+
+# RS0057: Symbol uses some oblivious reference types
+dotnet_diagnostic.RS0057.severity = none

src/VisualStudio/ExternalAccess/FSharp/.editorconfig

@@ -0,0 +1,6 @@
+[**]
+
+dotnet_public_api_analyzer.skip_namespaces = Microsoft.CodeAnalysis.ExternalAccess.FSharp.Internal
+
+# RS0057: Symbol uses some oblivious reference types
+dotnet_diagnostic.RS0057.severity = none