feat(core,web): player queue, play events and web player controller (M3, wip)

- core: PlayQueue with shuffle and repeat, PlayAttempt counting only
  time actually played, EventBuffer with batching and backoff, uuidv7
- web: Player over HTMLAudioElement with Media Session, preload of the
  next track, expired-link refresh, local and server playback state,
  hotkeys; PlayerProvider is not wired into the shell yet
- ru/en strings and icons for the player and Collection

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

apps/web/src/player/context.tsx

@@ -0,0 +1,74 @@
+import { createContext, useContext, useEffect, useState, useSyncExternalStore, type ReactNode } from 'react';
+
+import { useSession } from '../app/session';
+import { Player, type PlayerState } from './player';
+
+const PlayerContext = createContext<Player | null>(null);
+
+/** Плеер живёт, пока пользователь вошёл; горячие клавиши и сохранение при уходе со страницы. */
+export function PlayerProvider({ children }: { children: ReactNode }) {
+  const session = useSession();
+  const [player] = useState(() => new Player(session));
+
+  useEffect(() => {
+    void player.restore().catch(() => undefined);
+    const onHide = () => player.onHide();
+    const onVisibility = () => document.visibilityState === 'hidden' && onHide();
+    window.addEventListener('pagehide', onHide);
+    document.addEventListener('visibilitychange', onVisibility);
+    const onKey = (e: KeyboardEvent) => handleHotkey(player, e);
+    document.addEventListener('keydown', onKey);
+    return () => {
+      window.removeEventListener('pagehide', onHide);
+      document.removeEventListener('visibilitychange', onVisibility);
+      document.removeEventListener('keydown', onKey);
+      player.dispose();
+    };
+  }, [player]);
+
+  return <PlayerContext.Provider value={player}>{children}</PlayerContext.Provider>;
+}
+
+/** Пробел — пауза, ←/→ — ±10 с, Shift+←/→ — трек, L — лайк (docs/web.md). */
+export function handleHotkey(player: Player, e: KeyboardEvent) {
+  const target = e.target as HTMLElement | null;
+  if (target?.closest('input, textarea, select, [contenteditable="true"], [role="dialog"]')) return;
+  if (e.ctrlKey || e.metaKey || e.altKey) return;
+  const s = player.getState();
+  if (!s.track) return;
+  switch (e.key) {
+    case ' ':
+      if (target?.closest('button, a')) return; // пробел на кнопке нажимает её
+      e.preventDefault();
+      player.toggle();
+      break;
+    case 'ArrowLeft':
+      e.preventDefault();
+      if (e.shiftKey) player.prev();
+      else player.seek(s.positionMs - 10_000);
+      break;
+    case 'ArrowRight':
+      e.preventDefault();
+      if (e.shiftKey) player.next();
+      else player.seek(s.positionMs + 10_000);
+      break;
+    case 'l':
+    case 'L':
+    case 'д':
+    case 'Д':
+      e.preventDefault();
+      void player.react(s.track, s.track.reaction === 'like' ? null : 'like').catch(() => undefined);
+      break;
+  }
+}
+
+export function usePlayer(): Player {
+  const p = useContext(PlayerContext);
+  if (!p) throw new Error('usePlayer outside PlayerProvider');
+  return p;
+}
+
+export function usePlayerState(): PlayerState {
+  const p = usePlayer();
+  return useSyncExternalStore(p.subscribe, p.getState);
+}