music-lab: Suno API + MusicGen 듀얼 프로바이더 구조 구현

- suno_provider.py: Suno REST API 클라이언트 (곡 생성, 가사, 2변형 저장)
- local_provider.py: 기존 MusicGen 로직 분리
- main.py: provider 라우팅, /providers·/lyrics 엔드포인트 추가
- db.py: provider, lyrics, image_url, suno_id 컬럼 마이그레이션
- docker-compose.yml: SUNO_API_KEY 환경변수 추가

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

music-lab/app/db.py

@@ -24,6 +24,7 @@ def init_db() -> None:
                 audio_url  TEXT,
                 error      TEXT,
                 params     TEXT NOT NULL DEFAULT '{}',
+                provider   TEXT NOT NULL DEFAULT 'local',
                 created_at TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now')),
                 updated_at TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now'))
             )
@@ -46,11 +47,29 @@ def init_db() -> None:
                 file_path    TEXT NOT NULL DEFAULT '',
                 task_id      TEXT,
                 tags         TEXT NOT NULL DEFAULT '[]',
+                provider     TEXT NOT NULL DEFAULT 'local',
+                lyrics       TEXT NOT NULL DEFAULT '',
+                image_url    TEXT NOT NULL DEFAULT '',
+                suno_id      TEXT NOT NULL DEFAULT '',
                 created_at   TEXT NOT NULL DEFAULT (strftime('%Y-%m-%dT%H:%M:%fZ','now'))
             )
         """)
         conn.execute("CREATE INDEX IF NOT EXISTS idx_library_created ON music_library(created_at DESC)")
 
+        # 기존 테이블 마이그레이션 (컬럼 없으면 추가)
+        for col, default in [
+            ("provider", "'local'"), ("lyrics", "''"),
+            ("image_url", "''"), ("suno_id", "''"),
+        ]:
+            try:
+                conn.execute(f"ALTER TABLE music_library ADD COLUMN {col} TEXT NOT NULL DEFAULT {default}")
+            except sqlite3.OperationalError:
+                pass  # 이미 존재
+        try:
+            conn.execute("ALTER TABLE music_tasks ADD COLUMN provider TEXT NOT NULL DEFAULT 'local'")
+        except sqlite3.OperationalError:
+            pass
+
 
 # ── music_tasks CRUD ──────────────────────────────────────────────────────────
 
@@ -63,16 +82,17 @@ def _task_row_to_dict(r) -> Dict[str, Any]:
         "audio_url": r["audio_url"],
         "error":     r["error"],
         "params":    json.loads(r["params"]),
+        "provider":  r["provider"] if "provider" in r.keys() else "local",
         "created_at": r["created_at"],
         "updated_at": r["updated_at"],
     }
 
 
-def create_task(task_id: str, params: Dict[str, Any]) -> Dict[str, Any]:
+def create_task(task_id: str, params: Dict[str, Any], provider: str = "local") -> Dict[str, Any]:
     with _conn() as conn:
         conn.execute(
-            "INSERT INTO music_tasks (id, params) VALUES (?, ?)",
-            (task_id, json.dumps(params)),
+            "INSERT INTO music_tasks (id, params, provider) VALUES (?, ?, ?)",
+            (task_id, json.dumps(params), provider),
         )
         row = conn.execute("SELECT * FROM music_tasks WHERE id = ?", (task_id,)).fetchone()
     return _task_row_to_dict(row)
@@ -107,6 +127,7 @@ def get_task(task_id: str) -> Optional[Dict[str, Any]]:
 # ── music_library CRUD ────────────────────────────────────────────────────────
 
 def _track_row_to_dict(r) -> Dict[str, Any]:
+    keys = r.keys()
     return {
         "id":           r["id"],
         "title":        r["title"],
@@ -122,6 +143,10 @@ def _track_row_to_dict(r) -> Dict[str, Any]:
         "file_path":    r["file_path"],
         "task_id":      r["task_id"],
         "tags":         json.loads(r["tags"]) if r["tags"] else [],
+        "provider":     r["provider"] if "provider" in keys else "local",
+        "lyrics":       r["lyrics"] if "lyrics" in keys else "",
+        "image_url":    r["image_url"] if "image_url" in keys else "",
+        "suno_id":      r["suno_id"] if "suno_id" in keys else "",
         "created_at":   r["created_at"],
     }
 
@@ -138,8 +163,9 @@ def add_track(data: Dict[str, Any]) -> Dict[str, Any]:
             """
             INSERT INTO music_library
                 (title, genre, moods, instruments, duration_sec, bpm, key, scale,
-                 prompt, audio_url, file_path, task_id, tags)
-            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
+                 prompt, audio_url, file_path, task_id, tags,
+                 provider, lyrics, image_url, suno_id)
+            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
             """,
             (
                 data.get("title", ""),
@@ -155,6 +181,10 @@ def add_track(data: Dict[str, Any]) -> Dict[str, Any]:
                 data.get("file_path", ""),
                 data.get("task_id"),
                 json.dumps(data.get("tags", [])),
+                data.get("provider", "local"),
+                data.get("lyrics", ""),
+                data.get("image_url", ""),
+                data.get("suno_id", ""),
             ),
         )
         row = conn.execute("SELECT * FROM music_library WHERE rowid = last_insert_rowid()").fetchone()