Expose Solution and Project APIs for third-party tools

[kugushev]

Issue: #42449

Make the following APIs public to be used by third-party tools:

• Microsoft.CodeAnalysis.Host.IMetadataService
• Microsoft.CodeAnalysis.Host.IMetadataService.GetReference(string resolvedPath, Microsoft.CodeAnalysis.MetadataReferenceProperties properties) -> Microsoft.CodeAnalysis.PortableExecutableReference
• Microsoft.CodeAnalysis.Project.GetDocumentAsync(Microsoft.CodeAnalysis.DocumentId documentId, bool includeSourceGenerated = false, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.ValueTask<Microsoft.CodeAnalysis.Document>
• Microsoft.CodeAnalysis.Project.GetTextDocumentAsync(Microsoft.CodeAnalysis.DocumentId documentId, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.ValueTask<Microsoft.CodeAnalysis.TextDocument>
• Microsoft.CodeAnalysis.Solution.GetDocumentAsync(Microsoft.CodeAnalysis.DocumentId documentId, bool includeSourceGenerated = false, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.ValueTask<Microsoft.CodeAnalysis.Document>
• Microsoft.CodeAnalysis.Solution.GetTextDocumentAsync(Microsoft.CodeAnalysis.DocumentId documentId, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) -> System.Threading.Tasks.ValueTask<Microsoft.CodeAnalysis.TextDocument>
• Microsoft.CodeAnalysis.Solution.WithHasAllInformation(Microsoft.CodeAnalysis.ProjectId projectId, bool hasAllInformation) -> Microsoft.CodeAnalysis.Solution
• Microsoft.CodeAnalysis.Solution.WithRunAnalyzers(Microsoft.CodeAnalysis.ProjectId projectId, bool runAnalyzers) -> Microsoft.CodeAnalysis.Solution
• Microsoft.CodeAnalysis.SourceGeneratorTelemetry.ISourceGeneratorTelemetryCollectorWorkspaceService
• Microsoft.CodeAnalysis.SourceGeneratorTelemetry.ISourceGeneratorTelemetryCollectorWorkspaceService.CollectRunResult(Microsoft.CodeAnalysis.GeneratorDriverRunResult driverRunResult, Microsoft.CodeAnalysis.GeneratorDriverTimingInfo driverTimingInfo, System.Func<Microsoft.CodeAnalysis.ISourceGenerator, Microsoft.CodeAnalysis.Diagnostics.AnalyzerReference> getAnalyzerReference) -> void
• Microsoft.CodeAnalysis.AssemblyIdentityUtils
• static Microsoft.CodeAnalysis.AssemblyIdentityUtils.TryGetAssemblyIdentity(string filePath) -> Microsoft.CodeAnalysis.AssemblyIdentity

[CyrusNajmabadi]

All of this needs to go through API review. Please open an issue for that, explaining why each of these is needed. Thanks!