feat(charts): сбор статистики проигрываний и API чартов

- модели Track / TrackPlay / TrackLike (+ миграция add_charts)
- сбор проигрываний в now-playing-поллере: при смене трека на станции
  пишется TrackPlay (нормализация artist+song -> Track), fire-and-forget
  обогащение через MusicBrainz (album/releaseDate)
- ChartsModule: GET /charts/tracks (период day/week/month/all, ранг, тренд,
  проигрывания, станции, лайки), GET /charts/tracks/:id (метрики, таймлайны
  популярности и лайков по дням, топ станций, isLiked), POST/DELETE like
- OptionalAuthGuard для публичной детальной страницы с опц. userId

prisma/migrations/20250602130000_add_charts/migration.sql

@@ -0,0 +1,68 @@
+-- CreateTable: tracks
+CREATE TABLE "tracks" (
+    "id"           TEXT        NOT NULL,
+    "norm_key"     TEXT        NOT NULL,
+    "artist"       TEXT        NOT NULL,
+    "song"         TEXT        NOT NULL,
+    "cover_url"    TEXT,
+    "album"        TEXT,
+    "release_date" TIMESTAMPTZ,
+    "first_seen_at" TIMESTAMPTZ NOT NULL DEFAULT now(),
+    "enriched_at"  TIMESTAMPTZ,
+
+    CONSTRAINT "tracks_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable: track_plays
+CREATE TABLE "track_plays" (
+    "id"         TEXT        NOT NULL,
+    "track_id"   TEXT        NOT NULL,
+    "station_id" TEXT        NOT NULL,
+    "played_at"  TIMESTAMPTZ NOT NULL DEFAULT now(),
+
+    CONSTRAINT "track_plays_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateTable: track_likes
+CREATE TABLE "track_likes" (
+    "id"         TEXT        NOT NULL,
+    "track_id"   TEXT        NOT NULL,
+    "user_id"    TEXT        NOT NULL,
+    "created_at" TIMESTAMPTZ NOT NULL DEFAULT now(),
+
+    CONSTRAINT "track_likes_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE UNIQUE INDEX "tracks_norm_key_key" ON "tracks"("norm_key");
+
+-- CreateIndex
+CREATE INDEX "track_plays_track_id_played_at_idx" ON "track_plays"("track_id", "played_at");
+
+-- CreateIndex
+CREATE INDEX "track_plays_played_at_idx" ON "track_plays"("played_at");
+
+-- CreateIndex
+CREATE INDEX "track_plays_station_id_idx" ON "track_plays"("station_id");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "track_likes_track_id_user_id_key" ON "track_likes"("track_id", "user_id");
+
+-- CreateIndex
+CREATE INDEX "track_likes_track_id_idx" ON "track_likes"("track_id");
+
+-- AddForeignKey
+ALTER TABLE "track_plays" ADD CONSTRAINT "track_plays_track_id_fkey"
+    FOREIGN KEY ("track_id") REFERENCES "tracks"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "track_plays" ADD CONSTRAINT "track_plays_station_id_fkey"
+    FOREIGN KEY ("station_id") REFERENCES "stations"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "track_likes" ADD CONSTRAINT "track_likes_track_id_fkey"
+    FOREIGN KEY ("track_id") REFERENCES "tracks"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+
+-- AddForeignKey
+ALTER TABLE "track_likes" ADD CONSTRAINT "track_likes_user_id_fkey"
+    FOREIGN KEY ("user_id") REFERENCES "users"("id") ON DELETE CASCADE ON UPDATE CASCADE;

prisma/schema.prisma

@@ -14,9 +14,10 @@ model User {
   createdAt DateTime @default(now()) @map("created_at")
   updatedAt DateTime @updatedAt @map("updated_at")
 
-  favorites UserFavorite[]
-  history   PlayHistory[]
-  settings  UserSettings?
+  favorites   UserFavorite[]
+  history     PlayHistory[]
+  settings    UserSettings?
+  trackLikes  TrackLike[]
 
   @@map("users")
 }
@@ -51,9 +52,10 @@ model Station {
   createdAt        DateTime  @default(now()) @map("created_at")
   updatedAt        DateTime  @updatedAt @map("updated_at")
 
-  favorites  UserFavorite[]
-  history    PlayHistory[]
-  nowPlaying NowPlaying?
+  favorites   UserFavorite[]
+  history     PlayHistory[]
+  nowPlaying  NowPlaying?
+  trackPlays  TrackPlay[]
 
   @@index([isOnline])
   @@index([source])
@@ -112,3 +114,50 @@ model UserSettings {
 
   @@map("user_settings")
 }
+
+// Уникальный трек (нормализованный ключ artist+song)
+model Track {
+  id          String    @id @default(cuid())
+  normKey     String    @unique @map("norm_key")
+  artist      String
+  song        String
+  coverUrl    String?   @map("cover_url")
+  album       String?
+  releaseDate DateTime? @map("release_date")
+  firstSeenAt DateTime  @default(now()) @map("first_seen_at")
+  enrichedAt  DateTime? @map("enriched_at")
+
+  plays TrackPlay[]
+  likes TrackLike[]
+
+  @@map("tracks")
+}
+
+// Факт проигрывания трека на станции
+model TrackPlay {
+  id        String   @id @default(cuid())
+  trackId   String   @map("track_id")
+  track     Track    @relation(fields: [trackId], references: [id], onDelete: Cascade)
+  stationId String   @map("station_id")
+  station   Station  @relation(fields: [stationId], references: [id], onDelete: Cascade)
+  playedAt  DateTime @default(now()) @map("played_at")
+
+  @@index([trackId, playedAt])
+  @@index([playedAt])
+  @@index([stationId])
+  @@map("track_plays")
+}
+
+// Лайк трека пользователем
+model TrackLike {
+  id        String   @id @default(cuid())
+  trackId   String   @map("track_id")
+  track     Track    @relation(fields: [trackId], references: [id], onDelete: Cascade)
+  userId    String   @map("user_id")
+  user      User     @relation(fields: [userId], references: [id], onDelete: Cascade)
+  createdAt DateTime @default(now()) @map("created_at")
+
+  @@unique([trackId, userId])
+  @@index([trackId])
+  @@map("track_likes")
+}