Implemented the "createFile(at: with: )" function for the FileService service in the library target.

Test/Sources/Cases/Public/Services/FileServiceTests.swift

@@ -35,7 +35,7 @@ struct FileServiceTests {
         // WHEN
         try await service.copyFile(from: source, to: destination)
 
-        // THENn
+        // THEN
         #expect(spy.actions.count == 1)
         
         let action = try #require(spy.actions.last)
@@ -57,6 +57,37 @@ struct FileServiceTests {
         #expect(spy.actions.isEmpty == true)
     }
     
+    @Test(arguments: zip([URL.someNewFile],
+                         [Data("some data goes here...".utf8)]))
+    func createFile(with location: URL, and data: Data) async throws {
+        // GIVEN
+        let service = service(action: .createFile(location, data))
+        
+        // WHEN
+        try await service.createFile(at: location, with: data)
+        
+        // THEN
+        #expect(spy.actions.count == 1)
+        
+        let action = try #require(spy.actions.last)
+        
+        #expect(action == .fileCreated(location, data))
+    }
+    
+    @Test(arguments: [FileServiceError.itemAlreadyExists, .fileDataIsEmpty, .fileNotCreated])
+    func createFile(throws error: FileServiceError) async throws {
+        // GIVEN
+        let service = service(action: .error(error))
+        
+        // WHEN
+        // THEN
+        await #expect(throws: error) {
+            try await service.createFile(at: .someNewFile, with: .init())
+        }
+        
+        #expect(spy.actions.isEmpty == true)
+    }
+    
     @Test(arguments: [URL.someNewFolder, .someNewFile])
     func createFolder(with location: URL) async throws {
         // GIVEN