feat(v2): 模型设置（用户可调小模型/大模型/管线，/config + UI）

gateway/api.py

@@ -39,6 +39,7 @@ _router: Optional[Router] = None
 _pipeline: Optional["CollaborativePipeline"] = None
 _v2stats = V2Stats() if _V2_OK else None
 _review = None
+_settings = None
 
 
 def get_router() -> Router:
@@ -56,8 +57,23 @@ def get_review() -> "ReviewQueue":
     return _review
 
 
+def settings_store():
+    """用户可调整设置（懒加载单例）。"""
+    global _settings
+    if _settings is None:
+        from gateway.settings import load_settings
+        _settings = load_settings()
+    return _settings
+
+
+def rebuild_pipeline() -> None:
+    """清除管线单例，下次调用重建（配置改动后生效）。"""
+    global _pipeline
+    _pipeline = None
+
+
 def build_v2_pipeline(worker_cfg_override: Optional[dict] = None):
-    """从配置构建 v2 协作管线（architect + worker + pipeline）。
+    """从配置 + 用户设置构建 v2 协作管线（architect + worker + pipeline）。
 
     worker_cfg_override 可注入（测试/演示用 mock）。无 API key 时 /chat 会走
     本地降级路径（不崩溃）。
@@ -65,13 +81,27 @@ def build_v2_pipeline(worker_cfg_override: Optional[dict] = None):
     global _pipeline
     if _pipeline is None:
         cfg = load_config()
+        s = settings_store().to_dict() if _V2_OK else {}
         kb = KnowledgeBase()
-        architect = build_architect(cfg.get("architect", {}))
+
+        # architect（合并用户设置）
+        acfg = dict(cfg.get("architect", {}))
+        acfg.update(s.get("architect", {}))
+        architect = build_architect(acfg)
+
+        # worker（合并用户设置；backend 可 mock/openai/llama_server）
         wcfg = dict(cfg.get("worker", {}))
+        wcfg.update(s.get("worker", {}))
         if worker_cfg_override:
             wcfg.update(worker_cfg_override)
         worker = build_worker(wcfg, kb=kb)
-        _pipeline = build_pipeline(cfg, architect, worker)
+
+        # pipeline（合并用户设置）
+        cfg2 = dict(cfg)
+        pcfg = dict(cfg.get("pipeline", {}))
+        pcfg.update(s.get("pipeline", {}))
+        cfg2["pipeline"] = pcfg
+        _pipeline = build_pipeline(cfg2, architect, worker)
     return _pipeline
 
 
@@ -221,6 +251,31 @@ try:
             raise HTTPException(status_code=404, detail=f"审核记录不存在或已审核: {review_id}")
         return {"ok": True, "review_id": review_id, "verdict": verdict}
 
+    # ---------------- 模型设置（用户可调整） ----------------
+    @app.get("/config", tags=["settings"])
+    async def get_config():
+        """读取当前可调整设置（小模型 / 大模型 / 管线）。"""
+        return settings_store().to_dict()
+
+    @app.put("/config", tags=["settings"])
+    async def put_config(patch: dict):
+        """部分更新设置并重建管线。示例：
+        {"worker": {"backend": "openai", "base_url": "http://127.0.0.1:11434/v1", "temperature": 0.4}}
+        """
+        try:
+            merged = settings_store().update(patch)
+        except Exception as e:
+            raise HTTPException(status_code=400, detail=f"设置非法: {e}")
+        rebuild_pipeline()
+        return merged
+
+    @app.post("/config/reset", tags=["settings"])
+    async def reset_config():
+        """恢复默认设置并重建管线。"""
+        merged = settings_store().reset()
+        rebuild_pipeline()
+        return merged
+
     # ---------------- metrics ----------------
     @app.get("/metrics", tags=["system"])
     async def metrics():