feat: 实现 Tool Search 基础设施层（CORE_TOOLS 白名单 + TF-IDF 索引 + ExecuteTool + 搜索增强）

- 新增 CORE_TOOLS 白名单常量（31 个核心工具），重构 isDeferredTool 为白名单制判定
- 新建 TF-IDF 工具索引模块（toolIndex.ts），复用 localSearch.ts 算法函数
- 新建 ExecuteTool 跨 API provider 统一工具执行入口
- 增强 ToolSearchTool：TF-IDF 搜索路径、discover: 模式、并行搜索合并、文本模式回退
- 新增 27 个单元测试，precheck 零错误通过（4108 tests pass）

Co-Authored-By: glm-5.1[1m] <zai-org@claude-code-best.win>

packages/builtin-tools/src/tools/ExecuteTool/ExecuteTool.ts

@@ -0,0 +1,132 @@
+import { z } from 'zod/v4'
+import {
+  buildTool,
+  findToolByName,
+  type Tool,
+  type ToolDef,
+  type ToolUseContext,
+  type ToolResult,
+  type Tools,
+} from 'src/Tool.js'
+import { lazySchema } from 'src/utils/lazySchema.js'
+import { createUserMessage } from 'src/utils/messages.js'
+import { DESCRIPTION, getPrompt } from './prompt.js'
+import { EXECUTE_TOOL_NAME } from './constants.js'
+
+export const inputSchema = lazySchema(() =>
+  z.object({
+    tool_name: z
+      .string()
+      .describe(
+        'The exact name of the target tool to execute (e.g., "CronCreate", "mcp__server__action")',
+      ),
+    params: z
+      .record(z.string(), z.unknown())
+      .describe('The parameters to pass to the target tool'),
+  }),
+)
+type InputSchema = ReturnType<typeof inputSchema>
+
+export const outputSchema = lazySchema(() =>
+  z.object({
+    result: z.unknown(),
+    tool_name: z.string(),
+  }),
+)
+type OutputSchema = ReturnType<typeof outputSchema>
+
+export type Output = z.infer<OutputSchema>
+
+export const ExecuteTool = buildTool({
+  name: EXECUTE_TOOL_NAME,
+  searchHint: 'execute run invoke call a deferred tool by name with parameters',
+  maxResultSizeChars: 100_000,
+  isConcurrencySafe() {
+    return false
+  },
+  get inputSchema(): InputSchema {
+    return inputSchema()
+  },
+  get outputSchema(): OutputSchema {
+    return outputSchema()
+  },
+  async description() {
+    return DESCRIPTION
+  },
+  async prompt() {
+    return getPrompt()
+  },
+  async call(input, context, canUseTool, parentMessage, onProgress) {
+    const tools: Tools = context.options.tools ?? []
+
+    const targetTool = findToolByName(tools, input.tool_name)
+    if (!targetTool) {
+      return {
+        data: {
+          result: null,
+          tool_name: input.tool_name,
+        },
+        newMessages: [
+          createUserMessage({
+            content: `Tool "${input.tool_name}" not found. Use ToolSearch to discover available tools.`,
+          }),
+        ],
+      }
+    }
+
+    // Check permissions on the target tool
+    const permResult = await targetTool.checkPermissions?.(
+      input.params as Record<string, unknown>,
+      context,
+    )
+    if (permResult && permResult.behavior === 'deny') {
+      return {
+        data: {
+          result: null,
+          tool_name: input.tool_name,
+        },
+        newMessages: [
+          createUserMessage({
+            content: `Permission denied for tool "${input.tool_name}": ${permResult.message ?? 'Permission denied'}`,
+          }),
+        ],
+      }
+    }
+
+    // Delegate execution to the target tool
+    const targetResult: ToolResult<unknown> = await targetTool.call(
+      input.params as Record<string, unknown>,
+      context,
+      canUseTool,
+      parentMessage,
+      onProgress,
+    )
+
+    return {
+      ...targetResult,
+      data: {
+        result: targetResult.data,
+        tool_name: input.tool_name,
+      },
+    }
+  },
+  async checkPermissions() {
+    return {
+      behavior: 'passthrough',
+      message: 'ExecuteTool delegates permission to the target tool.',
+    }
+  },
+  renderToolUseMessage(input) {
+    return `Executing ${input.tool_name}...`
+  },
+  userFacingName() {
+    return 'ExecuteTool'
+  },
+  mapToolResultToToolResultBlockParam(content, toolUseID) {
+    return {
+      tool_use_id: toolUseID,
+      type: 'tool_result',
+      content: JSON.stringify(content),
+    }
+  },
+} satisfies ToolDef<InputSchema, Output>)