Changelog for CLI output overhaul

Author: JOJ0

docs/changelog.rst

@@ -38,6 +38,13 @@ New features
 - Metadata source plugin searches and lookups are now executed concurrently,
   speeding up lookups when multiple plugins (e.g. MusicBrainz and Spotify) are
   enabled.
+- :doc:`plugins/smartplaylist`: The ``splupdate`` command output is
+  restructured. The per-playlist summary now includes a track count. Per-track
+  details are shown only in ``DEBUG`` log level (``beet -v splupdate``). The
+  ``--pretend`` flag produces the same output but reports *"N playlists would be
+  updated"* instead of *"N playlists updated"*. The ``--format`` option allows
+  customizing the track line format. The ``--pretend-paths`` option was removed
+  since the per-track log line is now configurable. :bug:`6183`
 
 Bug fixes
 ~~~~~~~~~