Add reusable soundtrack pack and shared playlists

music/playlists/battle.json

@@ -0,0 +1,22 @@
+{
+  "Scene": "Battle",
+  "Musics": [
+    {
+      "MusicType": "Combat",
+      "MusicNames": [
+        "Aura of Decay",
+        "Circuit Dreams II",
+        "Crimson Echoes",
+        "Crimson Horizon",
+        "Glass Symphony",
+        "Hex Doom Cart",
+        "Iron Resonance",
+        "Iron Resonance II",
+        "Luminous Twilight",
+        "Rusty Frequencies",
+        "Skull Resonance",
+        "Venom's Embrace"
+      ]
+    }
+  ]
+}