Update roslyn to 5.5.0-2.26103.6

[dibarbet]

Updates Roslyn language server to version 5.5.0-2.26103.6.

Changes include:

• Fix workspace search always returning no results for first query
• Improve elimination of redundant evaluations during pattern matching operation
• Limit the FileSystemWatchers to one per drive root for DefaultFileChangeWatcher
• Reduce allocations during analysis result creation
• Set isReferenceAssembly to false if we found the implementation assembly
• Remove console title change from language server Program.cs

[dibarbet]

latest seems to have broken sourcelink

Expected substring: not "// Decompiled with ICSharpCode.Decompiler"
Received string:        "#region Assembly System.Console, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
// /usr/share/dotnet/packs/Microsoft.NETCore.App.Ref/8.0.23/ref/net8.0/System.Console.dll
// Decompiled with ICSharpCode.Decompiler 

[dibarbet]

Seems to be a timeout

2026-02-05 00:34:12.827 [debug] [textDocument/definition] [SourceLink] Navigating to symbol 'System.Console.WriteLine(string?)' from 'System.Console'.
2026-02-05 00:34:12.828 [debug] [textDocument/definition] [SourceLink] Symbol found in assembly path '/usr/share/dotnet/packs/Microsoft.NETCore.App.Ref/8.0.23/ref/net8.0/System.Console.dll'
2026-02-05 00:34:12.828 [debug] [textDocument/definition] [SourceLink] Symbol found in assembly path '/usr/share/dotnet/shared/Microsoft.NETCore.App/8.0.23/System.Console.dll'
2026-02-05 00:34:14.811 [debug] [textDocument/definition] [SourceLink] Timed out trying to download PDB from symbol server. Subsequent requests may succeed.

[JoeRobich]

latest seems to have broken sourcelink

Expected substring: not "// Decompiled with ICSharpCode.Decompiler"
Received string:        "#region Assembly System.Console, Version=8.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a
// /usr/share/dotnet/packs/Microsoft.NETCore.App.Ref/8.0.23/ref/net8.0/System.Console.dll
// Decompiled with ICSharpCode.Decompiler 

Running these tests using main and we are getting back MetadataAsSource. With this change we are now getting decompilation which I think would be preferred.