fix somethings

backend/app/config/settings.py

@@ -87,6 +87,18 @@ class Settings(BaseSettings):
     # no external worker needed. Switch to True only when a Celery worker is running.
     use_celery_worker: bool = Field(default=False, description="使用 Celery Worker 异步处理文档 (需要 Worker 运行中)")
 
+    # ── Perception crawl ──────────────────────────────────────────────────────
+    perception_crawl_timeout_seconds: int = Field(
+        default=120, description="HTTP timeout for regulatory source crawlers."
+    )
+    perception_max_events_per_source: int = Field(
+        default=100, description="Maximum events fetched per source per crawl run."
+    )
+    perception_diff_similarity_threshold: float = Field(
+        default=0.85,
+        description="Cosine similarity below which a paragraph is flagged as changed.",
+    )
+
     # Keep configuration setup explicit so runtime behavior is easy to reason about.
     api_host: str = Field(default="0.0.0.0", description="API服务地址")
     api_port: int = Field(default=8000, description="API服务端口")