refactor(aibox): 抽离B批12个工具类至tools包，附58个单测

B批（tools/）：迁移依赖子系统的12个工具类（CommandLineTool/SearchSkills/ReloadSkills/InstallSkill/CreateSkill/MemoryTool/MemoTool/UpdateIdentity/UpdateSoul/SaveMemoryAndEndConversation/SetProxy/GetProxy/AskUser），aibox.py减少~1739行

修复MemoryDatabase.get_recent_memories(limit=None)的SQL错误（既有bug，None传给LIMIT ?导致datatype mismatch）

171个单测全绿，循环依赖障碍消除：B批工具直接依赖subsystems而非反向依赖aibox.py

aibox/tools/proxy_tools.py

@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+"""
+tools.proxy_tools - 代理配置工具
+
+抽离自 aibox.py，包含 2 个工具：
+  - SetProxyTool : 设置 SOCKS5 代理
+  - GetProxyTool : 查看当前代理配置
+
+依赖：common (ConfigManager) + tools.base.Tool
+不反向依赖 aibox 任何符号。
+"""
+
+from typing import Dict
+
+from common import ConfigManager
+from .base import Tool
+
+
+class SetProxyTool(Tool):
+    """设置 SOCKS5 代理的工具"""
+
+    def get_name(self) -> str:
+        return "set_proxy"
+
+    def get_description(self) -> str:
+        return """设置智能体的 SOCKS5 代理配置。
+调用后所有 HTTP/HTTPS 请求（包括网页访问、API 调用）都会通过该代理。
+可随时修改，即时生效。"""
+
+    def get_parameters(self) -> Dict:
+        return {
+            "type": "object",
+            "properties": {
+                "host": {"type": "string", "description": "代理服务器地址，如 127.0.0.1"},
+                "port": {"type": "integer", "description": "代理端口，如 1080"},
+                "username": {"type": "string", "description": "用户名（可选）"},
+                "password": {"type": "string", "description": "密码（可选）"},
+                "enabled": {"type": "boolean", "description": "是否启用代理，默认 true"},
+                "save": {"type": "boolean", "description": "是否保存到配置文件（持久化），默认 true"}
+            },
+            "required": ["host", "port"]
+        }
+
+    def execute(self, host: str, port: int, username: str = None, password: str = None,
+                enabled: bool = True, save: bool = True, **kwargs) -> str:
+        config = ConfigManager()
+        config.set_proxy(host, port, username, password, enabled, save)
+        proxy_info = config.get_proxy_info()
+        data = {
+            "代理状态": "启用" if proxy_info["enabled"] else "禁用",
+            "服务器": f"{proxy_info['host']}:{proxy_info['port']}",
+            "认证": "有" if proxy_info.get("username") else "无",
+            "持久化": "已保存" if save else "仅内存"
+        }
+        return self.format_result(True, "代理设置成功", data)
+
+
+class GetProxyTool(Tool):
+    """查看当前代理配置"""
+
+    def get_name(self) -> str:
+        return "get_proxy"
+
+    def get_description(self) -> str:
+        return "查看当前 SOCKS5 代理配置信息"
+
+    def get_parameters(self) -> Dict:
+        return {"type": "object", "properties": {}}
+
+    def execute(self, **kwargs) -> str:
+        config = ConfigManager()
+        info = config.get_proxy_info()
+        if info["enabled"]:
+            data = {
+                "代理状态": "启用",
+                "服务器": f"{info['host']}:{info['port']}",
+                "认证": "有" if info.get("username") else "无"
+            }
+            return self.format_result(True, "当前代理配置", data)
+        else:
+            return "❌ 当前代理未启用，所有请求走直连。"