Build resource pack zip and drop it into .minecraft

Add archiver dep (v7 — v8 dropped the function-style default export
that the @types still describe) and a new src/installer-rp/pack.ts
that assembles the resource pack tree under tempDir/resourcepack/
and zips it to %appdata%/.minecraft/resourcepacks/<key>_musicquiz.zip.

The tree matches Minecraft 1.21+ painting variant + custom sound
conventions:

  pack.mcmeta                                           pack_format 34,
                                                        supported 34..75
  assets/musicquiz/sounds.json                          stream:true per track
  assets/musicquiz/sounds/track_NN.ogg                  from tempDir/music
  assets/musicquiz/textures/painting/cover_NN.png       from tempDir/painting

Music NN.ogg is renamed to track_NN.ogg at copy time so the sound
event ids stay readable. The painting_variant JSON definitions are
intentionally NOT generated here — those live in the data pack and
are owned by /op/datapack on the website.

Wire step 2-4 of the install IPC to call buildResourcepackZip with
the now-populated music/painting temp dirs. Step 2-5 is now just a
log line since buildResourcepackZip writes directly to the final
path.

Verified by a node smoke test: tempDir of two stub ogg files plus
two 256x256 PNGs produces a valid zip with the expected entries
and UTF-8 Korean strings in pack.mcmeta description.

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

package.json

@@ -12,6 +12,8 @@
     "dist:win": "tsc -p tsconfig.installer.json && electron-builder --win"
   },
   "dependencies": {
+    "@types/archiver": "^7.0.0",
+    "archiver": "^7.0.1",
     "ejs": "^3.1.10",
     "express": "^4.19.2",
     "express-session": "^1.18.0",