Fix EA layering for Razor.ExternalAccess (#77927)

Moves things to /Shared to ship in both MS.CA.EA.Razor and MS.CA.EA.Razor.Features

At some point we can rename MS.CA.EA.Razor to MS.CA.EA.Razor.EditorFeatures but I didn't bother with that in this PR
Shipping in both to not require dual insertion. We can fix this after a consuming change in Razor is inserted

Author: Andrew Hall

src/LanguageServer/ProtocolUnitTests/Completion/CompletionResolveTests.cs

@@ -16,9 +16,9 @@
 using Microsoft.CodeAnalysis.Options;
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.CodeAnalysis.Text;
-using Microsoft.VisualStudio.Text.Adornments;
 using Roslyn.LanguageServer.Protocol;
 using Roslyn.Test.Utilities;
+using Roslyn.Text.Adornments;
 using Xunit;
 using Xunit.Abstractions;
 using LSP = Roslyn.LanguageServer.Protocol;
@@ -423,7 +423,7 @@ private static VSInternalCompletionItem CreateResolvedCompletionItem(
             };
         }
 
-        expectedCompletionItem.Description = description.ToLSPElement();
+        expectedCompletionItem.Description = description;
         return expectedCompletionItem;
     }
 

src/LanguageServer/ProtocolUnitTests/Microsoft.CodeAnalysis.LanguageServer.Protocol.UnitTests.csproj

@@ -23,6 +23,7 @@
     <ProjectReference Include="..\..\Compilers\Core\Portable\Microsoft.CodeAnalysis.csproj" />
     <ProjectReference Include="..\..\Compilers\CSharp\Portable\Microsoft.CodeAnalysis.CSharp.csproj" />
     <ProjectReference Include="..\..\Compilers\VisualBasic\Portable\Microsoft.CodeAnalysis.VisualBasic.vbproj" />
+    <ProjectReference Include="..\..\EditorFeatures\Core\Microsoft.CodeAnalysis.EditorFeatures.csproj" />
     <ProjectReference Include="..\..\Interactive\Host\Microsoft.CodeAnalysis.InteractiveHost.csproj" />
     <ProjectReference Include="..\..\Scripting\Core\Microsoft.CodeAnalysis.Scripting.csproj" />
     <ProjectReference Include="..\..\Scripting\CSharp\Microsoft.CodeAnalysis.CSharp.Scripting.csproj" />

src/Tools/ExternalAccess/Razor/EditorFeatures/RazorDynamicFileInfoProviderWrapper.cs

@@ -14,7 +14,7 @@ namespace Microsoft.CodeAnalysis.ExternalAccess.Razor
     [Shared]
     [ExportMetadata("Extensions", new string[] { "cshtml", "razor", })]
     [Export(typeof(IDynamicFileInfoProvider))]
-    internal sealed class RazorDynamicFileInfoProviderWrapper : IDynamicFileInfoProvider
+    internal class RazorDynamicFileInfoProviderWrapper : IDynamicFileInfoProvider
     {
         private readonly Lazy<IRazorDynamicFileInfoProvider> _innerDynamicFileInfoProvider;
         private readonly object _attachLock = new object();

src/Tools/ExternalAccess/Razor/Features/AbstractRazorLspServiceFactory.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using Microsoft.CodeAnalysis.LanguageServer;
 

src/Tools/ExternalAccess/Razor/Features/AbstractRazorNotificationHandler.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.LanguageServer.Handler;
 
 namespace Microsoft.CodeAnalysis.ExternalAccess.Razor.Features;

src/Tools/ExternalAccess/Razor/Features/AbstractRazorRequestHandler.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.LanguageServer.Handler;
 using Microsoft.CommonLanguageServerProtocol.Framework;
 

src/Tools/ExternalAccess/Razor/Features/ExportRazorLspServiceFactoryAttribute.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Composition;
 using Microsoft.CodeAnalysis.LanguageServer;
 

src/Tools/ExternalAccess/Razor/Features/ExportRazorStatelessLspServiceAttribute.cs

@@ -2,6 +2,7 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
 using System.Composition;
 using Microsoft.CodeAnalysis.LanguageServer;
 

src/Tools/ExternalAccess/Razor/Features/IRazorLspServices.cs

@@ -2,6 +2,8 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System;
+using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 
 namespace Microsoft.CodeAnalysis.ExternalAccess.Razor.Features;

src/Tools/ExternalAccess/Razor/Features/IRazorRequestWrapper.cs

@@ -2,6 +2,9 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using System.Threading;
+using System.Threading.Tasks;
+
 namespace Microsoft.CodeAnalysis.ExternalAccess.Razor.Features;
 
 internal interface IRazorRequestWrapper