- Fix _delete_current_image: delegate to _remove_selected_files so
deletions are tracked in _removed_files / trim adjustments and
survive _refresh_files calls and session save/restore
- Fix _auto_save_session: reuse _current_session_id when available
instead of always creating new sessions. Clean up old autosave
sessions for the same destination to prevent unbounded accumulation.
- Fix signal cascade in _on_destination_changed: blockSignals around
_add_to_path_history to prevent currentIndexChanged re-entry
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>