LSP pull diagnostic handlers should handle None/Disabled option value for compiler and analyzer background analysis options

[mavasani]

Currently, neither of these handlers consider the below background analysis scope options for disabling compiler and/or analyzer diagnostics:

roslyn/src/Features/LanguageServer/Protocol/Features/Options/SolutionCrawlerOptionsStorage.cs

Lines 13 to 17 in bdbf1cb

	/// <summary>
	/// Option to turn configure background analysis scope for the current user.
	/// </summary>
	public static readonly PerLanguageOption2<BackgroundAnalysisScope> BackgroundAnalysisScopeOption = new(
	"dotnet_solution_crawler_background_analysis_scope", defaultValue: BackgroundAnalysisScope.Default, serializer: EditorConfigValueSerializer.CreateSerializerForEnum<BackgroundAnalysisScope>());

As this is not just a functionality issue, but also affects performance (unnecessarily running analyzers that users don't wish to see diagnostics for), we should prioritize fixing it.

[mavasani]

Turns out this already works as expected due to the pre-filtering of analyzers done below:

roslyn/src/Features/LanguageServer/Protocol/Features/Diagnostics/EngineV2/DiagnosticIncrementalAnalyzer_GetDiagnosticsForSpan.cs

Lines 105 to 106 in 5d944ea

	var stateSets = owner._stateManager
	.GetOrCreateStateSets(document.Project).Where(s => DocumentAnalysisExecutor.IsAnalyzerEnabledForProject(s.Analyzer, document.Project, owner.GlobalOptions));

which ends up checking the appropriate background analysis scope option below:

roslyn/src/Features/LanguageServer/Protocol/Features/Diagnostics/DocumentAnalysisExecutor_Helpers.cs

Lines 200 to 217 in 5d944ea

	public static bool IsAnalyzerEnabledForProject(DiagnosticAnalyzer analyzer, Project project, IGlobalOptionService globalOptions)
	{
	var options = project.CompilationOptions;
	if (options == null || analyzer == FileContentLoadAnalyzer.Instance || analyzer == GeneratorDiagnosticsPlaceholderAnalyzer.Instance)
	{
	return true;
	}
	if (analyzer.IsCompilerAnalyzer())
	{
	return globalOptions.GetBackgroundCompilerAnalysisScope(project.Language) != CompilerDiagnosticsScope.None;
	}
	// Check if user has disabled analyzer execution for this project or via options.
	if (!project.State.RunAnalyzers || globalOptions.GetBackgroundAnalysisScope(project.Language) == BackgroundAnalysisScope.None)
	{
	return false;
	}