Fixed
- Multi-directory scans no longer look stuck between directories. Each directory's
os.walk(disk spin-up + tree walk) emitted no progress, freezing the UI on the previous directory's last file — now it shows "Discovering files in<dir>…" at the start of every directory. - A scan no longer signals completion after each directory.
scan_directoryemitted a terminaldoneper directory (not just at the end), prematurely flipping the UI to idle mid-scan; it now emits a non-terminal update, and the single terminaldonecomes from the worker after all directories finish.