Attach a file to an upload control

Attaches files from the configured upload directory without going through the native OS file dialog. Set CAMOFOX_UPLOADS_DIR to a directory that contains the files (default: ~/.camofox/uploads). Two strategies are tried in order: (1) if an <input type="file"> is already present, call Playwright setInputFiles on it directly (works for hidden inputs); (2) otherwise arm a filechooser listener, activate the trigger element (ref or selector) via keyboard (focus + Enter) then a forced click as fallback, and call setFiles on the resulting chooser. Each path must be an absolute path that resolves inside the configured upload directory.