chore: optimize local crawler image build

docker/crawler/Dockerfile

@@ -3,6 +3,7 @@ FROM python:3.11-slim-bookworm
 ENV TZ=Asia/Shanghai \
     PYTHONUNBUFFERED=1 \
     PIP_NO_CACHE_DIR=1 \
+    PIP_INDEX_URL=https://pypi.tuna.tsinghua.edu.cn/simple \
     DQD_CONFIG_PATH=/app/config/settings.yaml \
     DQD_TASKS_FILE=/app/config/crawler_tasks.yaml \
     DQD_LOCK_DIR=/app/data/locks
@@ -22,8 +23,10 @@ RUN apt-get update \
 
 COPY requirements.txt /app/requirements.txt
 RUN python -m pip install --upgrade pip setuptools wheel \
-    && python -m pip install -r /app/requirements.txt \
-    && python -m playwright install --with-deps chromium
+    && python -m pip install -r /app/requirements.txt
+
+# API 型采集任务不依赖 Chromium。浏览器型采集需要时再在镜像内单独安装，
+# 避免本地首次构建因浏览器下载通道不可达而阻塞整个调度器。
 
 COPY . /app