feat: add 甜甜 Feishu bot for 苏瑶3号 knowledge-graph agent

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/core/config.py

@@ -100,6 +100,11 @@ class Settings(BaseSettings):
     SUYAO_APP_SECRET: str = ""
     SUYAO_AGENT_ID: str = ""  # 创建苏瑶后写入
 
+    # 甜甜飞书应用配置（独立 WS 连接，路由到苏瑶3号知识图谱 Agent）
+    TIANTIAN_APP_ID: str = ""
+    TIANTIAN_APP_SECRET: str = ""
+    TIANTIAN_AGENT_ID: str = ""  # 创建苏瑶3号后写入
+
     class Config:
         env_file = str(_ENV_PATH)
         case_sensitive = True