feat: 日报事件多新闻源入库(news_event.sources 列)

- ExtractedEvent 增加 sources 字段(主源居首去重,旧产物兜底 [source_id])
- extract_event(_async) 增加 sources 参数;run_event_extraction 读取
  deduped uniques 的 sources 透传
- reporter _load_events_from_dir 读取 sources → EventRow.sources
- news_event 建表加 sources TEXT 列;init_schema 幂等迁移旧表(捕获
  Duplicate column);save_report INSERT 写 JSON 多源
- 新增测试:ExtractedEvent/EventRow.sources 兜底与保序、_load_events_from_dir 多源

llm/extractor.py

@@ -188,10 +188,12 @@ def extract_event(
     *,
     template: PromptTemplate | None = None,
     max_attempts: int | None = None,
+    sources: list[str] | None = None,
 ) -> ExtractedEvent:
     """同步抽取单篇文章的事件(带重试)。
 
     max_attempts 为 None 时使用 config.max_attempts(来自 YAML/环境变量配置)。
+    sources 为该新闻全部来源(来自去重层多源记录);None 时兜底 [article.source_id]。
     """
     tpl = template or PromptTemplate()
     prompt = tpl.render(article)
@@ -208,6 +210,7 @@ def extract_event(
                 url_hash=article.url_hash,
                 title=article.title,
                 publish_time=article.publish_time,
+                sources=sources or [article.source_id],
                 event=event,
                 provider=config.provider,
                 model=config.model,
@@ -246,11 +249,13 @@ async def extract_event_async(
     *,
     template: PromptTemplate | None = None,
     max_attempts: int | None = None,
+    sources: list[str] | None = None,
     semaphore: asyncio.Semaphore | None = None,
 ) -> ExtractedEvent:
     """异步抽取(批处理用),与同步版逻辑等价。
 
     max_attempts 为 None 时使用 config.max_attempts。
+    sources 为该新闻全部来源;None 时兜底 [article.source_id]。
     """
     tpl = template or PromptTemplate()
     prompt = tpl.render(article)
@@ -268,6 +273,7 @@ async def extract_event_async(
                     url_hash=article.url_hash,
                     title=article.title,
                     publish_time=article.publish_time,
+                    sources=sources or [article.source_id],
                     event=event,
                     provider=config.provider,
                     model=config.model,