refactor(i18n): split locale files into per-namespace modules (Phase K) (#688)

Each src/locales/<lang>.ts (~1800 LOC) becomes a folder src/locales/<lang>/
with one module per i18n namespace (44 each) plus an index.ts barrel that
reassembles <lang>Translation in the original key order.

Mechanical, script-driven split with a JSON round-trip check: every
locale object is byte-identical to its pre-split form. i18n.ts is
unchanged — './locales/<lang>' now resolves to the folder index.

The per-namespace settings.ts files land ~440-460 LOC; a single i18n
namespace is the natural, non-arbitrary split unit for a flat string
table, so they are intentionally left whole.

src/locales/en/statistics.ts

@@ -0,0 +1,65 @@
+export const statistics = {
+  title: 'Statistics',
+  recentlyPlayed: 'Recently Played',
+  mostPlayed: 'Most Played Albums',
+  highestRated: 'Highest Rated Albums',
+  genreDistribution: 'Genre Distribution (Top 20)',
+  loadMore: 'Load more',
+  statArtists: 'Artists',
+  statArtistsTooltip: 'Album artists only — artists appearing only as a track-level artist (featured, guest, etc.) without their own album are not included.',
+  statAlbums: 'Albums',
+  statSongs: 'Songs',
+  statGenres: 'Genres',
+  statPlaytime: 'Total Playtime',
+  genreInsights: 'Genre Insights',
+  formatDistribution: 'Format Distribution',
+  formatSample: 'Sample of {{n}} tracks',
+  computing: 'Computing…',
+  genreSongs: '{{count}} Songs',
+  genreAlbums: '{{count}} Albums',
+  recentlyAdded: 'Recently Added',
+  decadeDistribution: 'Albums by Decade',
+  decadeAlbums_one: '{{count}} Album',
+  decadeAlbums_other: '{{count}} Albums',
+  decadeUnknown: 'Unknown',
+  lfmTitle: 'Last.fm Stats',
+  lfmTopArtists: 'Top Artists',
+  lfmTopAlbums: 'Top Albums',
+  lfmTopTracks: 'Top Tracks',
+  lfmPlays: '{{count}} plays',
+  lfmPeriodOverall: 'All Time',
+  lfmPeriod7day: '7 Days',
+  lfmPeriod1month: '1 Month',
+  lfmPeriod3month: '3 Months',
+  lfmPeriod6month: '6 Months',
+  lfmPeriod12month: '12 Months',
+  lfmNotConnected: 'Connect Last.fm in Settings to see your stats.',
+  lfmRecentTracks: 'Recent Scrobbles',
+  lfmNowPlaying: 'Now Playing',
+  lfmJustNow: 'just now',
+  lfmMinutesAgo: '{{n}}m ago',
+  lfmHoursAgo: '{{n}}h ago',
+  lfmDaysAgo: '{{n}}d ago',
+  topRatedSongs: 'Top Rated Songs',
+  topRatedArtists: 'Top Rated Artists',
+  noRatedSongs: 'No rated songs yet. Rate songs in album or playlist view.',
+  noRatedArtists: 'No rated artists yet.',
+  exportShare: 'Share',
+  exportTitle: 'Share Top Albums',
+  exportSubtitle: 'Generate a shareable image of your most-played albums.',
+  exportFormat: 'Format',
+  exportFormatStory: 'Story',
+  exportFormatSquare: 'Square',
+  exportFormatTwitter: 'Twitter Card',
+  exportGrid: 'Grid',
+  exportGridLabel: '{{n}}×{{n}}',
+  exportPreview: 'Preview',
+  exportGenerate: 'Generate',
+  exportSave: 'Save image…',
+  exportCancel: 'Cancel',
+  exportFooterLabel: 'Top Albums',
+  exportNotEnough: 'Need at least {{count}} albums in your library for a {{n}}×{{n}} grid.',
+  exportSaving: 'Saving…',
+  exportSaved: 'Saved.',
+  exportSaveFailed: 'Could not save the image.',
+};