Wire up 음악퀴즈_test manifest to local test artifacts

Fill empty platform.downloadUrl / modsFolder / resourcepackPath / serverPath
so the test pack drives a complete installer flow end-to-end.

Test artifacts (gitignored, must be present locally under file/):
  file/platforms/fabric-installer.jar  (real fabric installer 1.0.1)
  file/mods/music-quiz/music-quiz-test-mod.jar  (stub fabric mod)
  file/resourcepacks/music-quiz.zip  (stub resourcepack)
  file/maps/music-quiz-map.zip  (stub world)
  file/servers/music-quiz-server.zip  (stub server with eula.txt=false to exercise EULA popup)

mcVersion "26.1.2" left as user authored; not a real MC version,
so 게임 실행 단계는 실패할 수 있음 — installer flow itself runs through.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

manifest/music-quiz.json

@@ -2,14 +2,15 @@
   "name": "음악퀴즈_test",
   "mcVersion": "26.1.2",
   "platform": {
-    "type": "fabric"
+    "type": "fabric",
+    "downloadUrl": "/fabric-installer.jar"
   },
-  "modsFolder": "",
-  "resourcepackPath": "",
+  "modsFolder": "music-quiz",
+  "resourcepackPath": "music-quiz.zip",
   "serverMinRam": 2048,
   "serverMaxRam": 8192,
   "clientMinRam": 4096,
   "clientRecommendedRam": 8192,
   "mapPath": "music-quiz-map.zip",
-  "serverPath": ""
+  "serverPath": "music-quiz-server.zip"
 }