feat: add Suyao Feishu bot and per-agent memory config support

- Create suyao_app_service.py and suyao_ws_handler.py for 苏瑶 Feishu bot
- Add SUYAO_APP_ID/SUYAO_APP_SECRET/SUYAO_AGENT_ID config fields
- Fix node config extraction bug (n.get("config") → n.get("data")) in all WS handlers
- Add _build_memory_config_from_node() to support per-agent memory settings
  (max_history_messages, vector_memory_top_k, persist_to_db, etc.)
- Create 苏瑶1号 (Plan A: long context), 苏瑶2号 (Plan B: emotion tracking),
  苏瑶3号 (Plan C: knowledge graph + RAG) agents with different memory strategies

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

backend/app/api/agent_chat.py

@@ -26,6 +26,7 @@ from app.agent_runtime import (
     AgentLLMConfig,
     AgentToolConfig,
     AgentBudgetConfig,
+    AgentMemoryConfig,
     AgentStep,
     AgentOrchestrator,
     OrchestratorAgentConfig,
@@ -293,6 +294,7 @@ async def chat_with_agent(
 
     uid = current_user.id
     mem_scope = f"{uid}:{agent_id}" if uid else str(agent_id)
+    memory_cfg = _build_memory_config_from_node(agent_node_cfg)
     config = AgentConfig(
         name=agent.name,
         system_prompt=system_prompt,
@@ -306,6 +308,7 @@ async def chat_with_agent(
             include_tools=agent_node_cfg.get("tools", []),
             exclude_tools=agent_node_cfg.get("exclude_tools", []),
         ),
+        memory=memory_cfg,
         budget=budget,
         user_id=uid,
         memory_scope_id=mem_scope,
@@ -360,6 +363,7 @@ async def chat_with_agent_stream(
 
     uid = current_user.id
     mem_scope = f"{uid}:{agent_id}" if uid else str(agent_id)
+    memory_cfg = _build_memory_config_from_node(agent_node_cfg)
     config = AgentConfig(
         name=agent.name,
         system_prompt=system_prompt,
@@ -373,6 +377,7 @@ async def chat_with_agent_stream(
             include_tools=agent_node_cfg.get("tools", []),
             exclude_tools=agent_node_cfg.get("exclude_tools", []),
         ),
+        memory=memory_cfg,
         budget=budget,
         user_id=uid,
         memory_scope_id=mem_scope,
@@ -400,3 +405,14 @@ def _find_agent_node_config(nodes: list) -> Dict[str, Any]:
         if typ in ("agent", "llm", "template"):
             return node.get("data") or {}
     return {}
+
+
+def _build_memory_config_from_node(agent_node_cfg: dict) -> AgentMemoryConfig:
+    """从 Agent 工作流节点配置中提取记忆配置。"""
+    return AgentMemoryConfig(
+        max_history_messages=int(agent_node_cfg.get("memory_max_history", 20)),
+        vector_memory_top_k=int(agent_node_cfg.get("memory_vector_top_k", 5)),
+        persist_to_db=bool(agent_node_cfg.get("memory_persist", True)),
+        vector_memory_enabled=bool(agent_node_cfg.get("memory_vector_enabled", True)),
+        learning_enabled=bool(agent_node_cfg.get("memory_learning", True)),
+    )