feat(queue): add Now-Playing Info tab with artist bio, song credits and Bandsintown tour dates (#244)

* feat(queue): add Now-Playing Info tab with artist bio, song credits and Bandsintown tour dates

A third tab in the right-side queue panel surfaces context for the
currently playing track:

- Artist card: image + biography from Subsonic getArtistInfo (Last.fm
  "Read more on Last.fm" anchor stripped), with read-more toggle that
  only appears when the bio actually overflows the 4-line clamp.
- Song info: contributor credits from OpenSubsonic contributors[]
  rendered stacked (name prominent, role muted). Section is hidden
  entirely on servers without contributor support, and rows that just
  re-state the main artist under role "artist" are filtered out.
- On tour: optional Bandsintown integration (opt-in, off by default).
  HTTP fetch + JSON parsing happen entirely on the Rust side; the
  frontend wrapper deduplicates concurrent calls and caches results in
  RAM for the session. Limited to 5 events with a "Show N more" toggle.
  When the toggle is off, the section becomes an in-place opt-in card
  with a privacy info-tooltip explaining what data is sent — same
  tooltip is also exposed on the matching toggle in Settings.

Caching: artist info and song detail are memoised by stable IDs across
component remounts, so jumping between tracks of the same album/artist
does not refire the network calls.

Implementation notes:
- Bandsintown app_id "js_app_id" — arbitrary strings (e.g. "psysonic")
  now return HTTP 403 from rest.bandsintown.com; js_app_id is the ID
  Bandsintown's own embeddable widget uses and is broadly accepted.
- Tour items use negative left/right margins so the date badge stays
  visually aligned with the section title while the hover background
  extends slightly past the section edges.
- New i18n namespace nowPlayingInfo across all 8 locales (en, de, fr,
  nl, zh, nb, ru, es) including pluralised "Show N more" forms.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* fix(now-playing-info): switch nested flex-columns to block layout to stop content-dependent drift

Repeated reports of the Tour and Song-info sections rendering at
inconsistent x-positions (sometimes left of the section title,
sometimes centred, sometimes correctly aligned) — varying by artist,
sidebar width, and even whether "Show more" was clicked.

Root cause: nested flex-direction: column containers
(.np-info → .np-info-section → .np-info-tour / .np-info-credits) where
the cross-axis (horizontal) sizing on WebKitGTK occasionally inherits
the intrinsic min-content of the longest child. With one
"Naherholungsgebiet/Freizeitgelände Lago Alfredo"-style venue name
that overflows the sidebar, the parent ul gets pushed past 100% width
and the entire layout drifts. min-width: 0 on every level didn't help
because cross-axis stretch in flex-column ignores it for content-driven
overflow.

Fix: collapse all the section/list containers to display: block. Block
layout is content-agnostic — children always render at 100% parent
width, left-aligned, deterministically. Spacing between siblings now
uses the lobotomy selector (`> * + * { margin-top }`).

Only the tour item itself stays flex (badge ↔ meta horizontal layout),
and that one still has overflow: hidden + flex: 1 1 0 + min-width: 0
on the meta column to truncate venue/place text with ellipsis.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Psychotoxical <dev@psysonic.app>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/locales/en.ts

@@ -608,6 +608,8 @@ export const enTranslation = {
     discordTemplateLargeText: 'Album tooltip (largeText)',
     nowPlayingEnabled: 'Show in Now Playing',
     nowPlayingEnabledDesc: 'Broadcast your currently playing track to the server\'s live listener view. Disable to stop sending playback data.',
+    enableBandsintown: 'Bandsintown tour dates',
+    enableBandsintownDesc: 'Show upcoming concerts for the current artist in the Info tab. Data is fetched from the public Bandsintown API.',
     lyricsServerFirst: 'Prefer server lyrics',
     lyricsServerFirstDesc: 'Check server-provided lyrics (embedded tags, sidecar files) before querying LRCLIB. Disable to use LRCLIB first.',
     enableNeteaselyrics: 'Netease Cloud Music lyrics',
@@ -1051,6 +1053,30 @@ export const enTranslation = {
     showDuration: 'Show duration',
     showRemainingTime: 'Show remaining time',
   },
+  nowPlayingInfo: {
+    tab: 'Info',
+    empty: 'Play something to see info',
+    artist: 'Artist',
+    songInfo: 'Song info',
+    onTour: 'On tour',
+    noTourEvents: 'No upcoming shows',
+    tourLoading: 'Loading…',
+    poweredByBandsintown: 'Tour data via Bandsintown',
+    bioReadMore: 'Read more',
+    bioReadLess: 'Show less',
+    showMoreTours_one: 'Show {{count}} more',
+    showMoreTours_other: 'Show {{count}} more',
+    showLessTours: 'Show less',
+    enableBandsintownPrompt: 'See upcoming tour dates?',
+    enableBandsintownPromptDesc: 'Optional. Loads concerts for the current artist via the public Bandsintown API.',
+    enableBandsintownPrivacy: 'When enabled, the name of the currently playing artist is sent to the Bandsintown API to fetch tour dates. No account or personal data leaves your device.',
+    enableBandsintownAction: 'Enable',
+    role: {
+      artist: 'Artist',
+      albumArtist: 'Album artist',
+      composer: 'Composer',
+    },
+  },
   songInfo: {
     title: 'Song Info',
     songTitle: 'Title',