Theme system as data: qbz_theme registry (36 themes + auto/custom)
resolved from the shared ui_prefs slug into a themeJson document;
QbzTheme rebound to it so the whole app repaints live (OLED->Light
probe-verified). Full subnav (8 sections + Share logs footer);
Appearance 1:1 (theme dropdown with dark/light filter, ambient/titlebar
rows in their real home, typography, library visuals, window chrome,
tray via tray_settings.db, renderer); Integrations 1:1 (MusicBrainz,
Last.fm 2-step browser connect + authed state, ListenBrainz token
validate, Discord toggle -> live DiscordRpc.set_enabled). Offline/Local
Library/Blacklist/Developer render honest placeholders.
km