The library is going live as the canonical store, synced to a second machine
via Syncthing. Track locations were stored absolute and only remapped at import,
so on a second machine (where Syncthing mounts the folder at a different path)
every location would break.
- lintunes/paths.py: to_relative/to_absolute. Locations are stored relative to
the data dir and resolved back on load, applied only at the json_storage
boundary (save_tracks/load_library). Track.location stays absolute in memory,
so the player, tagging, and art code are unchanged. The data dir and the music
move together inside one synced tree, so paths resolve wherever it's mounted —
no per-machine music_root config. Absolute paths in older library.json files
still load (back-compat).
- tests/test_round15.py: helper round-trips, back-compat, and a machine-2
scenario (save under root A, load the copied tree under root B).
- TASKS.md/tasks-done.md: mark the data-dir move + real import done; log the
benign exit-time Qt/FFmpeg teardown segfault.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>