feat: 动态工具插件化——引入可扩展的 DynamicToolRegistry

[devin-ai-integration]

Summary

将动态工具系统从"写死的联合类型 + 静态记录"重构为可扩展的注册表模式。

之前 BuiltinDynamicToolName = "image_generate" 是封闭联合，新增工具必须修改核心类型。
重构后新增工具只需：

import { dynamicToolRegistry } from "@codenexus/shared/dynamicTools";

dynamicToolRegistry.register({
  name: "local_search",
  namespace: "codenexus",
  label: "Local Search",
  description: "Searches workspace files by content",
  requiresApproval: false,
  inputSchema: {
    type: "object",
    properties: { query: { type: "string" } },
    required: ["query"],
  },
});

注册后工具自动出现在设置的启用/禁用列表中，并在下一次 Codex 会话启动时被注入。

Scope

• packages/shared/src/dynamicTools.ts — 核心重构：DynamicToolRegistry 类 + 单例 + builtin 自注册 + 旧导出兼容层
• packages/shared/src/localSettings.ts — enabledByName 类型从 Record<BuiltinDynamicToolName, boolean> 放宽为 Record<string, boolean>
• packages/shared/src/__tests__/dynamicTools.test.ts — 新增 6 个注册表测试，总计 36 个测试通过

Verification

• pnpm run format:check
• pnpm run lint
• pnpm run typecheck（4 个子包全部通过）
• pnpm run test — 36 tests passed

Screenshots or Recordings

N/A（无 UI 变更）

Notes

• 旧 API（BUILTIN_DYNAMIC_TOOL_DEFINITIONS、buildBuiltinDynamicToolSpecs、filterEnabledBuiltinDynamicToolNames、normalizeBuiltinDynamicToolName）标记 @deprecated 但仍可用，调用侧无需立即修改。
• DynamicToolRegistry 是纯内存结构，渲染层和主进程各自维护独立实例；当前 dynamicToolRegistry 单例在模块加载时注册内置工具。
• 后续可在此基础上加：工具配置 UI（设置页列出所有 registered tools）、工具 JSON manifest 文件加载、远程 MCP 工具自动注册等。

Link to Devin session: https://app.devin.ai/sessions/26c0ad2a81d3440eaa67d6f4feb3df33
Requested by: @QinQinChina

[devin-ai-integration]

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