feat(tracklist): multi-select + psyDnD, filter/sort, settings & UI polish

- AlbumTrackList: extract TrackRow as React.memo, selection state moved to
  selectionStore (Zustand) for O(1) re-renders per toggle; Ctrl/Cmd+Click
  enters select mode; drag selected tracks as {type:'songs'} payload;
  selection clears on outside click or song-list change
- QueuePanel: handle 'songs' multi-track drop type; whitelist drag types to
  suppress drop feedback for non-queue drags (lyrics grip etc.)
- AlbumDetail + PlaylistDetail: filter/sort toolbar (title/artist, natural
  order); disc grouping bypassed when sorted; playlist reorder DnD disabled
  while filter active
- useTracklistColumns: 'known' field auto-shows newly added columns for
  existing users
- PlayerBar: mute/unmute restores previous volume via premuteVolumeRef
  instead of hardcoded 0.7
- Settings/Input: reset buttons restyled as RotateCcw icon above card,
  matching HomeCustomizer layout
- i18n: filterSongs, sortNatural, sortByTitle, sortByArtist keys across
  all 7 locales
- components.css: album-card-title/artist nowrap to keep playlist grid
  cards uniform height

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/store/selectionStore.ts

@@ -0,0 +1,13 @@
+import { create } from 'zustand';
+
+interface SelectionState {
+  selectedIds: Set<string>;
+  setSelectedIds: (update: (prev: Set<string>) => Set<string>) => void;
+  clearAll: () => void;
+}
+
+export const useSelectionStore = create<SelectionState>((set) => ({
+  selectedIds: new Set<string>(),
+  setSelectedIds: (update) => set((s) => ({ selectedIds: update(s.selectedIds) })),
+  clearAll: () => set({ selectedIds: new Set() }),
+}));