Implement Phase 2 Frontend and Phase 3 Data Enrichment

- Initialize React+Vite Frontend with Ant Design Dashboard.
- Implement Data Enrichment: ReccoBeats (Audio Features) and Spotify (Genres).
- Update Database Schema via Alembic Migrations.
- Add Docker support (Dockerfile, docker-compose.yml).
- Update README with hosting instructions.

backend/app/services/spotify_client.py

@@ -3,6 +3,7 @@ import base64
 import time
 import httpx
 from fastapi import HTTPException
+from typing import List, Dict, Any
 
 SPOTIFY_TOKEN_URL = "https://accounts.spotify.com/api/token"
 SPOTIFY_API_BASE = "https://api.spotify.com/v1"
@@ -68,3 +69,26 @@ class SpotifyClient:
             if response.status_code != 200:
                 return None
             return response.json()
+
+    async def get_artists(self, artist_ids: List[str]) -> List[Dict[str, Any]]:
+        """
+        Fetches artist details (including genres) for a list of artist IDs.
+        Spotify allows up to 50 IDs per request.
+        """
+        if not artist_ids:
+            return []
+
+        token = await self.get_access_token()
+        ids_param = ",".join(artist_ids)
+
+        async with httpx.AsyncClient() as client:
+            response = await client.get(
+                f"{SPOTIFY_API_BASE}/artists",
+                params={"ids": ids_param},
+                headers={"Authorization": f"Bearer {token}"},
+            )
+            if response.status_code != 200:
+                print(f"Error fetching artists: {response.text}")
+                return []
+
+            return response.json().get("artists", [])