feat: 增强 core/agents 工具和 API

- 新增 loop.py Agent 运行循环
- 优化 memory.py 记忆模块
- 扩展 api/routes.py 接口
- 更新 tools 模块：builtin.py, manager.py, __init__.py
- 新增 .env.example 配置示例
- 更新 requirements.txt 依赖

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

core/agents/tools/__init__.py

@@ -21,19 +21,55 @@ from agents.tools.builtin import (
 from agents.tools.manager import ToolManager
 
 
-def create_default_registry() -> ToolRegistry:
+def create_default_registry(use_sandbox: bool = False) -> ToolRegistry:
     """Create a tool registry with default tools.
 
+    Args:
+        use_sandbox: Whether to use sandbox for shell execution
+
     Returns:
         Tool registry with built-in tools
     """
     registry = ToolRegistry()
     # Register built-in tools
-    for tool in get_builtin_tools():
+    for tool in get_builtin_tools(use_sandbox=use_sandbox):
         registry.register(tool)
     return registry
 
 
+# Import sandbox tools from nanobot (optional)
+try:
+    from nanobot.agent.tools.sandbox_execution import (
+        SandboxType,
+        SandboxCodeExecutionTool,
+        SandboxBashTool,
+        get_sandbox_tools,
+    )
+    from nanobot.agent.tools.bwrap_sandbox import (
+        BwrapSandbox,
+        get_bwrap_sandbox,
+        execute_in_bwrap,
+    )
+    from nanobot.agent.tools.gvisor_sandbox import (
+        GvisorSandbox,
+        get_gvisor_sandbox,
+        execute_in_gvisor,
+    )
+    SANDBOX_AVAILABLE = True
+except ImportError as e:
+    SandboxType = None
+    SandboxCodeExecutionTool = None
+    SandboxBashTool = None
+    get_sandbox_tools = None
+    BwrapSandbox = None
+    get_bwrap_sandbox = None
+    execute_in_bwrap = None
+    GvisorSandbox = None
+    get_gvisor_sandbox = None
+    execute_in_gvisor = None
+    SANDBOX_AVAILABLE = False
+
+
 __all__ = [
     "Tool",
     "ToolRegistry",
@@ -48,4 +84,16 @@ __all__ = [
     "CalculatorTool",
     "GetTimeTool",
     "BashTool",
+    # Sandbox tools
+    "SANDBOX_AVAILABLE",
+    "SandboxType",
+    "SandboxCodeExecutionTool",
+    "SandboxBashTool",
+    "get_sandbox_tools",
+    "BwrapSandbox",
+    "GvisorSandbox",
+    "get_bwrap_sandbox",
+    "get_gvisor_sandbox",
+    "execute_in_bwrap",
+    "execute_in_gvisor",
 ]