Optimize file enumeration to skip build directories during traversal

[Copilot]

The current file enumeration in EntityFileDiscovery.cs enumerates all files including those in bin, obj, .git, and node_modules, then filters them out post-traversal. This is inefficient for large projects.

Changes

• Replaced RecurseSubdirectories = true with manual recursion that filters directories before descending
• Applied optimization to both SearchDirectoryForEntitiesAsync and SearchForBaseClassFiles
• Extracted max search depth as named constant MaxSearchDepth

Before

var options = new EnumerationOptions { RecurseSubdirectories = true };
foreach (var csFile in Directory.EnumerateFiles(searchDir, "*.cs", options))
{
    var pathSegments = fullPath.Split(Path.DirectorySeparatorChar);
    if (pathSegments.Any(s => s is "bin" or "obj" or ".git" or "node_modules"))
        continue;  // Skip after enumeration
}

After

foreach (var subDir in Directory.EnumerateDirectories(currentDir))
{
    var dirName = Path.GetFileName(subDir);
    if (dirName is "bin" or "obj" or ".git" or "node_modules")
        continue;  // Skip before descending
    
    await SearchDirectoryRecursiveAsync(subDir, ...);
}

This prevents the file system from enumerating potentially thousands of files in build artifacts and dependency directories.

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[Copilot]

Pull request overview

This PR optimizes file enumeration in EntityFileDiscovery.cs by implementing manual directory recursion that filters out build and version control directories (bin, obj, .git, node_modules) before traversing them, rather than enumerating all files first and filtering afterward.

Changes:

• Replaced RecurseSubdirectories = true with manual recursion in both entity and base class file discovery methods
• Introduced MaxSearchDepth constant to limit recursion depth in base class file searches
• Added early exit optimizations in SearchForBaseClassFilesRecursive to stop searching once all files are found

---

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[Copilot]

The SearchDirectoryForEntitiesAsync method is now just a thin wrapper that directly calls SearchDirectoryRecursiveAsync without adding any additional logic. Consider either removing this wrapper and calling SearchDirectoryRecursiveAsync directly from DiscoverEntityFilesAsync (line 49), or add the depth parameters to SearchDirectoryRecursiveAsync and initialize them in this wrapper method to make it serve a clear purpose.

Suggested change

	{
	{
	// Basic validation to ensure we do not attempt to search with invalid inputs.
	if (string.IsNullOrWhiteSpace(searchDir) ||
	entityTypeNames == null ||
	entityFiles == null)
	{
	return;
	}
	// Avoid starting a recursive search on a directory that does not exist.
	if (!System.IO.Directory.Exists(searchDir))
	{
	return;
	}

[Copilot]

The SearchDirectoryRecursiveAsync method lacks depth tracking and maximum depth enforcement, unlike SearchForBaseClassFilesRecursive which has these safeguards. This creates an inconsistency and potential risk of unbounded recursion if the file system contains symbolic links or deeply nested directory structures. Consider adding currentDepth and maxDepth parameters to match the pattern used in SearchForBaseClassFilesRecursive, and add an early return check similar to line 461.

[Copilot]

SearchDirectoryRecursiveAsync should check if all entities have been found and return early, similar to the optimization in SearchForBaseClassFilesRecursive (lines 484-487, 502-505). This would prevent unnecessary traversal once all entity files have been discovered. Consider adding a check after processing files and before recursing into subdirectories: if (entityTypeNames.All(entityFiles.ContainsKey)) return;

[Copilot]

The documentation for MaxSearchDepth indicates it's only used for "base class files", but this constant should also apply to entity file searching in SearchDirectoryRecursiveAsync to prevent unbounded recursion. Update the documentation to reflect that this constant applies to all recursive file search operations in this class.

Suggested change

	/// Maximum recursion depth when searching for base class files to prevent infinite recursion
	/// Maximum recursion depth for recursive file search operations in this class to prevent infinite recursion

[Copilot]

The file WorkspaceTypeDiscovery.cs (lines 61-71) still uses the old pattern of RecurseSubdirectories = true with post-traversal filtering. For consistency and performance, consider applying the same optimization pattern used in this PR to that file as well.

[Copilot]

Directory name filtering uses pattern matching which is case-sensitive ("bin" or "obj" or ".git" or "node_modules"). On Windows, directory names are case-insensitive, so "Bin", "BIN", "Obj", "OBJ" would not be filtered out. Consider using case-insensitive comparison, similar to how path comparisons are handled elsewhere in the codebase (e.g., line 226 uses StringComparison.OrdinalIgnoreCase). Example: if (dirName.Equals("bin", StringComparison.OrdinalIgnoreCase) || dirName.Equals("obj", StringComparison.OrdinalIgnoreCase) || ...)

Suggested change

	if (dirName is "bin" or "obj" or ".git" or "node_modules")
	if (string.Equals(dirName, "bin", System.StringComparison.OrdinalIgnoreCase)
	|| string.Equals(dirName, "obj", System.StringComparison.OrdinalIgnoreCase)
	|| string.Equals(dirName, ".git", System.StringComparison.OrdinalIgnoreCase)
	|| string.Equals(dirName, "node_modules", System.StringComparison.OrdinalIgnoreCase))

[Copilot]

Directory name filtering uses pattern matching which is case-sensitive ("bin" or "obj" or ".git" or "node_modules"). On Windows, directory names are case-insensitive, so "Bin", "BIN", "Obj", "OBJ" would not be filtered out. Consider using case-insensitive comparison, similar to how path comparisons are handled elsewhere in the codebase (e.g., line 226 uses StringComparison.OrdinalIgnoreCase). Example: if (dirName.Equals("bin", StringComparison.OrdinalIgnoreCase) || dirName.Equals("obj", StringComparison.OrdinalIgnoreCase) || ...)

Suggested change

	if (dirName is "bin" or "obj" or ".git" or "node_modules")
	if (dirName.Equals("bin", System.StringComparison.OrdinalIgnoreCase)
	|| dirName.Equals("obj", System.StringComparison.OrdinalIgnoreCase)
	|| dirName.Equals(".git", System.StringComparison.OrdinalIgnoreCase)
	|| dirName.Equals("node_modules", System.StringComparison.OrdinalIgnoreCase))

[Copilot]

This foreach loop immediately maps its iteration variable to another variable - consider mapping the sequence explicitly using '.Select(...)'.