fix: file free dangling pointer

src/file.c

@@ -123,7 +123,7 @@ void file_write(const char *path, const StringArray *lines) {
   fclose(file_pointer);
 }
 
-void file_free(const File *file) {
+void file_free(File *file) {
   if (!file->error) {
     free(file->content);
   }