Motivation

• Provide a visible current/total progress count in the Library Compression tab so users can see numeric progress in addition to the progress bar and existing log output.

Description

• Add a progress_var tk.StringVar and a ttk.Label bound to it in LibraryCompressionPanel in main_gui.py to display "Progress: X / Y".
• Reset the progress label to "Progress: 0 / 0" in _set_running when a run starts.
• Update the progress_callback inside _mirror_library to set the progress bar maximum/value and update progress_var with f"Progress: {completed} / {total}" on the UI thread.

Testing

• No automated tests were run for this change.

Codex Task