style(core): Add missing newline at end of fileManipulate.ts

Fixed formatting issue identified by Biome linter to ensure consistent
code style across the project.

src/core/file/fileManipulate.ts

@@ -367,4 +367,4 @@ const manipulators: Record<string, FileManipulator> = {
 export const getFileManipulator = (filePath: string): FileManipulator | null => {
   const ext = path.extname(filePath);
   return manipulators[ext] || null;
-};
+};