Fixed self._state → self._state_machine (latent AttributeError when
copying video to clipboard from popout context menu).
Rewrote copy logic to use QMimeData with file URL + image data,
matching main_window's Ctrl+C. For streaming URLs, resolves to the
cached local file. Added Copy Image URL entry for the source URL.
behavior change: clipboard copy now includes file URL; new context
menu entry for URL copy; video copy no longer crashes.
pax
c210c4b44a