Add the second of the four switchable now-playing bar layouts plus the
4-layout architecture behind it.
ShellState.npb-mode (0=New, 1=Classic) drives mode-conditional columns in
PlayerBar; the transport cluster is extracted into TransportControls.slint and
IconButton/PlayButton into primitives/BarControls (PlayButton gains a `circle`
prop) so both layouts share them without duplicating the popups. The choice
persists via UiPrefs.npb_mode ("new"/"classic") — restored on startup, written
on the "Now Playing view" menu select.
Classic = the Tauri arrangement: transport LEFT (plain play glyph, leading
track-info, inline add-to-playlist + favorite-with-state), glass song card
CENTRE, actions + volume RIGHT. SongCard.glass is a contained card capped at a
fixed 520px; the audio stamp is ABSOLUTELY pinned to the card's right edge
(cover 56 | song info that truncates with ellipsis | stamp 140) so it stays
flush right regardless of the text layout. Track info fires from both the
title click and the transport (i). Classic uses the full-size audio stamp; the
backend LED reads PIPEWIRE.
cc
vicrodh
1ad0d7c169