feat: Integrate WaterCrawl.dev as a new knowledge base provider (#16396)

Co-authored-by: crazywoola <427733928@qq.com>

api/services/auth/api_key_auth_factory.py

@@ -17,6 +17,10 @@ class ApiKeyAuthFactory:
                 from services.auth.firecrawl.firecrawl import FirecrawlAuth
 
                 return FirecrawlAuth
+            case AuthType.WATERCRAWL:
+                from services.auth.watercrawl.watercrawl import WatercrawlAuth
+
+                return WatercrawlAuth
             case AuthType.JINA:
                 from services.auth.jina.jina import JinaAuth