Implemented the "exists(at: )" function for the FileService service in the module target.

Sources/Library/Protocols/FileServicing.swift

@@ -1,9 +1,23 @@
 import Foundation
 
-protocol FileServicing {
+public protocol FileServicing {
     
-    // MARK: Properties
+    // MARK: Computed
     
     var currentFolder: URL { get async }
     
+    // MARK: Functions
+    
+    func exists(at url: URL) async throws (FileServiceError) -> Bool
+    
+}
+
+// MARK: - Errors
+
+public enum FileServiceError: Error, Equatable {
+    case folderNotCreated
+    case folderNotDeleted
+    case urlAlreadyExists
+    case urlNotExists
+    case urlNotFileURL
 }