music(chord): 加 yopu.co 吉他谱自动抓取（sidecar 模式）

复刻 ../guitar 的功能：
- 新加 chord-fetcher sidecar（python 3.11 + chromium + selenium），跟 main 同 pod 共享 PVC
- yopu.py v2：搜「和弦谱」→ 进 view → 选 谱面样式=功能谱 + 和弦样式=级数名 → 截 sheet-container → PIL 裁白边
- music backend 加 POST /api/pieces/:id/chord/fetch + GET /chord/status，转发 sidecar 并把 png import 成 image attachment role=chord
- 前端 chord tab 在没图时显示「自动抓取」按钮，点了 polling 状态、完成后刷新
- CI build 两个 image（music + music-chord），rollout 同步切版本

.gitea/workflows/deploy-music.yml

@@ -19,6 +19,7 @@ jobs:
       APP: music
       NS: cube-music
       IMAGE: registry.famzheng.me/mochi/music
+      CHORD_IMAGE: registry.famzheng.me/mochi/music-chord
     steps:
       - uses: actions/checkout@v4
 
@@ -38,13 +39,19 @@ jobs:
           npm ci
           npm run build
 
-      - name: Build & push image
+      - name: Build & push images
         env:
           REGISTRY_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
         run: |
           echo "$REGISTRY_TOKEN" | docker login registry.famzheng.me -u mochi --password-stdin
+          # main app
           docker build -f "apps/$APP/Dockerfile" -t "$IMAGE:${{ steps.tag.outputs.sha }}" .
           docker push "$IMAGE:${{ steps.tag.outputs.sha }}"
+          # chord-fetcher sidecar (python + chromium)
+          docker build -f "apps/$APP/chord/Dockerfile" \
+            -t "$CHORD_IMAGE:${{ steps.tag.outputs.sha }}" \
+            "apps/$APP/chord"
+          docker push "$CHORD_IMAGE:${{ steps.tag.outputs.sha }}"
 
       - name: Initialize K8s resources
         run: |
@@ -52,5 +59,7 @@ jobs:
 
       - name: Roll out to k3s
         run: |
-          kubectl -n "$NS" set image "deploy/$APP" "$APP=$IMAGE:${{ steps.tag.outputs.sha }}"
-          kubectl -n "$NS" rollout status "deploy/$APP" --timeout=120s
+          kubectl -n "$NS" set image "deploy/$APP" \
+            "$APP=$IMAGE:${{ steps.tag.outputs.sha }}" \
+            "chord-fetcher=$CHORD_IMAGE:${{ steps.tag.outputs.sha }}"
+          kubectl -n "$NS" rollout status "deploy/$APP" --timeout=300s