feat(beaver): 完成Task Team功能v1实现，重构后端架构支持统一内核

新增内部Task系统，包括验证、反馈门控机制，实现自动质量验证
(通过率>=0.75)和用户反馈闭环(satisfied/revise/abandon)。

实现Agent Team v1协调器，支持sequence/parallel/dag执行策略，
sub-agent复用主AgentLoop，每个run使用独立memory snapshot。

建立Skill学习pipeline，包含draft/审核/发布/回滚完整生命周期，
通过Task验证通过且用户满意才生成学习候选。

重构目录结构，移除third_party依赖，建立统一engine内核，
所有agent共享运行时基础组件。

更新ContextBuilder清理provider消息字段，增强SkillContext版本管理，
集成TaskExecutionPlanner和TaskSkillResolver实现技能解析机制。

app-instance/backend/beaver/interfaces/gateway/main.py

@@ -21,6 +21,16 @@ from beaver.interfaces.channels import ChannelAdapter, ChannelManager
 from beaver.services.agent_service import AgentService
 
 
+def _validate_gateway_service(service: AgentService) -> None:
+    """Fail fast on injected service objects that do not satisfy gateway needs."""
+
+    handler = getattr(service, "handle_inbound_message", None)
+    if not callable(handler):
+        raise TypeError(
+            "Gateway requires a service with an async 'handle_inbound_message(inbound)' method"
+        )
+
+
 async def _cleanup_owned_service(
     service: AgentService,
     *,
@@ -125,6 +135,7 @@ async def run_gateway(
     """
 
     attached_service = service or AgentService(workspace=workspace, config_path=config_path)
+    _validate_gateway_service(attached_service)
     if channel_manager is not None and channels is not None:
         raise ValueError("Pass either channel_manager or channels, not both")
     if bus is not None: