[Bug]: Top-level brace-scoped `using` declaration with object initializer containing `string` collection initializer with `;`, `{`, or `}` tokens in items break brace highlighting

[just-ero]

Issue Description

This seems to be an edge case that has not been noticed.
In a top-level file, a brace-scoped using declaration with an object initialized which contains a collection initializer containing strings will break brace highlighting if any of the strings contain a ;, {, }, or // (maybe others?) token.

Steps to Reproduce

1. Open a top-level C# file.

2. using MyClass braceScopedInstance = new() // Target-typed or not does not appear to matter.
   {
       Strings = { ";" } // <~ Brace highlighting starts breaking here.
   };
   
   class MyClass : IDisposable
   {
       public List<string> Strings { get; }
   
       public void Dispose() { }
   }
   

Expected Behavior

Brace highlighting continues to be correct.

Actual Behavior

Visual Studio Code highlights the closing braces after the ";" incorrectly. It also believes that the first opening brace does not have a closing match.

The behavior is slightly different for {, } and // tokens.

The expected behavior happens when the code is within any kind of scope:

// Something as simple as this in the top-level file is enough.
{
    using MyClass braceScopedInstance = new()
    {
        Strings = { ";" } // Brace highlighting is correct.
    };
}

Logs

extension-logs.zip

C# Trace Logs

c#-trace-logs.txt

C# LSP Trace Logs

c#-lsp-trace-logs.txt

Environment information

VSCode version: 1.85.2 C# Extension: 2.15.30 Using OmniSharp: false

Dotnet Information

.NET SDK:
 Version:   8.0.100-rc.2.23502.2
 Commit:    0abacfc2b6

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22631
 OS Platform: Windows
 RID:         win-x64
 Base Path:   C:\Program Files\dotnet\sdk\8.0.100-rc.2.23502.2\

.NET workloads installed:
 [wasi-experimental]
   Installation Source: SDK 8.0.100-rc.2
   Manifest Version:    8.0.0-rc.2.23479.6/8.0.100-rc.2
   Manifest Path:       C:\Program Files\dotnet\sdk-manifests\8.0.100-rc.2\microsoft.net.workload.mono.toolchain.current\8.0.0-rc.2.23479.6\WorkloadManifest.json
   Install Type:              Msi


Host:
  Version:      8.0.0-rc.2.23479.6
  Architecture: x64
  Commit:       0b25e38ad3

.NET SDKs installed:
  8.0.100-rc.2.23502.2 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 8.0.0-rc.2.23480.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.26 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.15 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.0-rc.2.23479.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 6.0.26 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 8.0.0-rc.2.23479.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
  None

Environment variables:
  Not set

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

Visual Studio Code Extensions

Extension	Author	Version	Folder Name
csdevkit	ms-dotnettools	1.3.6	ms-dotnettools.csdevkit-1.3.6-win32-x64
csharp	ms-dotnettools	2.15.30	ms-dotnettools.csharp-2.15.30-win32-x64
vscode-dotnet-runtime	ms-dotnettools	2.0.1	ms-dotnettools.vscode-dotnet-runtime-2.0.1
vscodeintellicode-csharp	ms-dotnettools	0.1.26	ms-dotnettools.vscodeintellicode-csharp-0.1.26-win32-x64

[JoeRobich]

This seems to be an issue with the C# textmate grammar.