Settings — own Audio categories + Queue Settings consolidation (#1130)

* refactor(settings): promote Normalization and Track transitions to own Audio categories

Pull Normalization and Track transitions out of the combined Playback
section into their own top-level SettingsSubSection categories, placed
directly under Audio Output Device. Both follow the established reusable
pattern (SettingsSubSection header + title-less SettingsGroup inside a
single-group settings-card, so the frame-collapse CSS applies).

- New TrackTransitionsBlock extracted from PlaybackBehaviorBlock; the
  latter now holds only the Queue behaviour toggle (slated to move to
  Personalisation).
- NormalizationBlock's SettingsGroup is now title-less; the section
  header and description name it.
- Split the single audio search-index row into three (Normalization /
  Track transitions / Playback) so crossfade/replaygain/lufs keywords
  focus the right section.

* refactor(settings): consolidate Queue Settings under Personalisation, drop Audio Playback section

Combine Queue Display Mode and Queue Toolbar under one 'Queue Settings'
category in the Personalisation tab, and move the Queue behaviour toggle
(preservePlayNextOrder) there from Audio. The now-empty Audio Playback
section is removed.

- New 'Queue Settings' SettingsSubSection holds three titled groups:
  Queue Display Mode, Queue behaviour, and (advanced-only) Queue Toolbar.
  The toolbar group keeps its reset, now via a new optional 'action' slot
  on SettingsGroup (+ .settings-group-title-action CSS).
- Delete PlaybackBehaviorBlock; its single toggle is inlined.
- Search index: drop the audio 'playbackTitle' row; the personalisation
  queue row now points at 'queueSettingsTitle' with merged keywords.
- i18n: add settings.queueSettingsTitle to all 9 locales.

* fix(settings): align queue-toolbar separator label and restore Advanced badge

- QueueToolbarCustomizer: the separator row rendered a 1px rule where other
  rows have a 16px icon, so its label sat shifted left. Reserve the full
  16px icon column (1px rule centred) so the label lines up. (Preexisting.)
- SettingsGroup gains an optional 'advanced' flag rendering the Advanced
  badge; badge + action now share a right-aligned title-end slot
  (.settings-group-title-end), so the badge sits just left of the reset
  button. Restores the Advanced indicator the Queue Toolbar lost when it
  moved from a SettingsSubSection into a group.

* fix(audio): hide the output-device category on macOS instead of showing a notice

Playback is pinned to the system default on macOS, so the picker showed a
notice explaining it does nothing there. Gate the whole Audio Output Device
category out on macOS (`!IS_MACOS` in AudioTab) and drop the now-dead notice
branch + the `audioOutputDeviceMacNotice` string from all 9 locales. The
device-probe hook already short-circuits on macOS, so no work is wasted.

* refactor(settings): box the sidebar customizer groups consistently

The sidebar display toggles sat as a bare div and looked unfinished. Box
them in a SettingsGroup, with the nav-item drag list in a second group.

Render the groups directly in the sub-section content (no settings-card
wrapper) — matching the other Personalisation customizers, which use bare
SettingsGroups. Also drop the settings-card around Queue Settings for the
same reason, so every Personalisation section's boxes share one width and
inset instead of the card-wrapped ones sitting narrower/indented.

* docs(settings): changelog, what's new, and credits for the settings reorg (#1130)

Fold the Audio/Personalisation reorganization into the existing
'Settings — consistent grouped layout' changelog entry (now #1126 + #1130)
and the matching What's New highlight, and add a consolidated settings-
refactor line to the contributor credits.

src/components/settings/settingsTabs.ts

@@ -37,7 +37,8 @@ export const SETTINGS_INDEX: SearchIndexEntry[] = [
   { tab: 'audio',          titleKey: 'settings.hiResTitle',               keywords: 'hi-res hires resampling bit depth sample rate dsd 24bit' },
   { tab: 'audio',          titleKey: 'settings.eqTitle',                  keywords: 'equalizer eq bass treble autoeq filter pre-gain' },
   { tab: 'audio',          titleKey: 'settings.playbackRateTitle',        keywords: 'speed playback rate tempo pitch varispeed preserve corrected time stretch' },
-  { tab: 'audio',          titleKey: 'settings.playbackTitle',            keywords: 'playback crossfade autodj auto dj smart crossfade gapless replaygain replay gain volume trim silence' },
+  { tab: 'audio',          titleKey: 'settings.normalization',            keywords: 'normalization normalisation loudness volume leveling level replaygain replay gain lufs pre-gain' },
+  { tab: 'audio',          titleKey: 'settings.transitionsTitle',         keywords: 'track transitions crossfade autodj auto dj smart crossfade gapless blend fade trim silence' },
   { tab: 'lyrics',         titleKey: 'settings.lyricsSourcesTitle',       keywords: 'lyrics sources providers lrclib netease server youlyplus karaoke standard static' },
   { tab: 'lyrics',         titleKey: 'settings.sidebarLyricsStyle',       keywords: 'lyrics scroll style classic apple music' },
   { tab: 'integrations',   titleKey: 'musicNetwork.title',                keywords: 'last.fm lastfm libre.fm rocksky listenbrainz maloja scrobble scrobbling music network' },
@@ -47,7 +48,7 @@ export const SETTINGS_INDEX: SearchIndexEntry[] = [
   { tab: 'personalisation',titleKey: 'settings.sidebarTitle',             keywords: 'sidebar nav navigation items reorder customize' },
   { tab: 'personalisation',titleKey: 'settings.artistLayoutTitle',        keywords: 'artist page layout sections order' },
   { tab: 'personalisation',titleKey: 'settings.homeCustomizerTitle',      keywords: 'mainstage home page customize sections' },
-  { tab: 'personalisation',titleKey: 'settings.queueToolbarTitle',        keywords: 'queue toolbar buttons reorder customize shuffle save load' },
+  { tab: 'personalisation',titleKey: 'settings.queueSettingsTitle',       keywords: 'queue settings display mode list playlist timeline toolbar buttons reorder customize shuffle save load behaviour behavior preserve play next order' },
   { tab: 'personalisation',titleKey: 'settings.playlistLayoutTitle',     keywords: 'playlist page layout add songs import csv download zip cache offline suggestions controls hide show' },
   { tab: 'personalisation',titleKey: 'settings.playerBarTitle',          keywords: 'player bar playback favorites stars rating lastfm love equalizer mini player controls hide show' },
   { tab: 'appearance',     titleKey: 'settings.libraryGridMaxColumnsTitle', keywords: 'grid columns album artist playlist cards layout appearance performance scroll paint' },