MP3 CSV Tagger v1.4.0 — append export (desktop 1.3.0, Android 1.1.0)

Append export — build one library CSV folder by folder

Library exports can now merge into an existing CSV instead of replacing it, on both the desktop program (v1.3.0) and the Android app (v1.1.0):

• Export one folder to a CSV, then append scans of other folders into the same file.
• Rows are keyed by FilePath: a re-scanned file's row updates in place (same position, fresh values); rows outside the scan are kept untouched; new files append at the end.
• New tag columns are added at the end of the header; a column the scan doesn't produce — including one you added by hand — keeps its values even on updated rows.
• If the CSV has no FilePath column, rows fall back to keying on the file-name column, with a clear warning.
• Both front-ends report rows added / updated / kept and columns added after each append.

Desktop: export --append on the CLI, and "Append to an existing CSV…" in the Files-tab Export dialog. Android: "Append to existing CSV" in the Export dialog (pick the target via SAF); the app's export now also writes the FilePath column the merge keys on.

Assets: the Linux standalone build of the desktop program (v1.3.0) and the Android APK (v1.1.0, signed with the app's per-app release key, same signer as v1.0.0).