feat(app-instance): 集成Beaver后端并更新配置管理

集成新的Beaver后端服务到应用实例中，替换原有的nanobot实现。

主要变更包括：
- 在Dockerfile和环境配置中添加Beaver相关路径和配置变量
- 更新工作目录结构从.nanobot到.beaver
- 实现Beaver引擎加载器，支持配置文件加载和工具组装
- 添加内置工具如ListDirectoryTool、ReadFileTool、SearchFilesTool
- 更新消息处理流程，支持通道适配器和网关模式
- 重构技能系统，支持显式工具提示和嵌入式检索
- 改进错误处理和生命周期管理

此变更使应用实例能够使用统一的Beaver后端进行AI代理运行时管理。

app-instance/backend/beaver/tools/runtime/executor.py

@@ -12,12 +12,14 @@
 from __future__ import annotations
 
 import json
-from typing import Any
+from typing import TYPE_CHECKING, Any
 
-from beaver.engine.providers.base import ToolCallRequest
 from beaver.tools.base import ToolContext, ToolResult
 from beaver.tools.registry.tool_registry import ToolRegistry
 
+if TYPE_CHECKING:
+    from beaver.engine.providers.base import ToolCallRequest
+
 
 class ToolExecutor:
     """统一执行单个 tool call。"""
@@ -80,16 +82,17 @@ class ToolExecutor:
 
     @staticmethod
     def _normalize_tool_call(tool_call: ToolCallRequest | dict[str, Any]) -> tuple[str, dict[str, Any]]:
-        if isinstance(tool_call, ToolCallRequest):
-            return tool_call.name, dict(tool_call.arguments)
-
-        function = tool_call.get("function")
-        if isinstance(function, dict):
-            name = function.get("name")
-            arguments = function.get("arguments", {})
+        if not isinstance(tool_call, dict):
+            name = getattr(tool_call, "name", None)
+            arguments = getattr(tool_call, "arguments", {})
         else:
-            name = tool_call.get("name")
-            arguments = tool_call.get("arguments", {})
+            function = tool_call.get("function")
+            if isinstance(function, dict):
+                name = function.get("name")
+                arguments = function.get("arguments", {})
+            else:
+                name = tool_call.get("name")
+                arguments = tool_call.get("arguments", {})
 
         if not name:
             raise ValueError("Tool call is missing a tool name")
@@ -104,8 +107,8 @@ class ToolExecutor:
 
     @staticmethod
     def _extract_tool_name(tool_call: ToolCallRequest | dict[str, Any]) -> str:
-        if isinstance(tool_call, ToolCallRequest):
-            return str(tool_call.name or "unknown")
+        if not isinstance(tool_call, dict):
+            return str(getattr(tool_call, "name", None) or "unknown")
         function = tool_call.get("function")
         if isinstance(function, dict) and function.get("name"):
             return str(function["name"])