feat(settings): cross-tab fuzzy search + tab restructure polish (#263)

Cross-tab settings search:
- Static SETTINGS_INDEX covering every sub-section of every tab, with
  free-form keywords per entry so "scrobble" finds Last.fm, "replay gain"
  finds Playback, etc.
- matchScore() does substring-first ranking, falls back to a char-in-order
  fuzzy match so typos still yield hits.
- Active tab keeps its in-place hide/show filter; matches from other tabs
  render at the top as a clickable "In other tabs" list (tab badge +
  sub-section title). Clicking clears the query, switches tab, and scrolls
  + opens the target sub-section.
- All 8 locales updated: new searchOtherTabs key, searchNoResults reworded
  (old "try another tab" hint is now handled by the list itself).

Settings restructure polish:
- "Next Track Buffering" moved from Audio to the Storage tab — sits
  between Offline Library and Downloads.
- Storage tab label renamed across 8 locales: "Storage & Downloads" →
  "Offline & Cache" (equivalents per locale). nb locale was missing
  tabStorage entirely; added. Tab id stays 'storage' to avoid breaking
  persisted state.
- Library tab: Random Mix sub-section now opens by default (previously
  both sub-sections started collapsed) and is renamed "Random Mix
  Blacklist" in all 8 locales — the section is entirely a blacklist
  config, the old title was misleading.
- Lyrics tab:
  * Standard / YouLyPlus rows use the same toggle style as the "Show
    lyrics as static text" row and stack vertically. Order swapped so
    YouLyPlus is first.
  * Provider list (Server / LRCLIB / Netease) moved to appear directly
    under the Standard toggle as its sub-item, indented, instead of after
    the static-text toggle.
  * Classic / Apple Music-like rows likewise rebuilt as vertical toggle
    rows.
- One pre-existing typo carried in from #261 fixed along the way: the
  openAddServerInvite handler in Settings referenced the renamed tab id
  'server' (pre-#259) — now 'servers'. [Note: already landed in PR #262,
  keeping this commit clean of that.]

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

src/locales/en.ts

@@ -690,7 +690,7 @@ export const enTranslation = {
     aboutContributorsLabel: 'Contributors',
     showChangelogOnUpdate: "Show 'What's New' on update",
     showChangelogOnUpdateDesc: "Show a discreet changelog banner above Now Playing after an update. Click opens the release notes; X dismisses it.",
-    randomMixTitle: 'Random Mix',
+    randomMixTitle: 'Random Mix Blacklist',
     randomMixBlacklistTitle: 'Custom Filter Keywords',
     randomMixBlacklistDesc: 'Songs are excluded when any keyword matches their genre, title, album, or artist (active when the checkbox above is on).',
     randomMixBlacklistPlaceholder: 'Add keyword…',
@@ -698,7 +698,7 @@ export const enTranslation = {
     randomMixBlacklistEmpty: 'No custom keywords added yet.',
     randomMixHardcodedTitle: 'Built-in keywords (active when checkbox is on)',
     tabAudio: 'Audio',
-    tabStorage: 'Storage & Downloads',
+    tabStorage: 'Offline & Cache',
     tabAppearance: 'Appearance',
     tabLibrary: 'Library',
     tabServers: 'Servers',
@@ -709,7 +709,8 @@ export const enTranslation = {
     aboutContributorsCount_one: '{{count}} contribution',
     aboutContributorsCount_other: '{{count}} contributions',
     searchPlaceholder: 'Search settings…',
-    searchNoResults: 'No matching settings in this tab. Try another tab.',
+    searchNoResults: 'No settings match your search.',
+    searchOtherTabs: 'In other tabs',
     integrationsPrivacyTitle: 'Privacy notice',
     integrationsPrivacyBody: 'All integrations on this tab are <strong>opt-in</strong> and send data to external services or to your Navidrome server when enabled. Last.fm receives your listening history, Discord shows the currently playing track in your profile, Bandsintown is queried per artist to fetch tour dates, and the Now-Playing share publishes your current track to other users of your Navidrome server. If you don\'t want any of this, simply leave the corresponding section disabled.',
     homeCustomizerTitle: 'Home Page',