feat: 新增MCP Server功能，支持文档全局检索工具

[nl8590687]

feat: 新增MCP Server功能，支持文档全局检索工具

由于依赖mcp-go依赖对go版本最低要求为 go 1.23，因此go build的最低版本将被升级到 go 1.23

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已通过Dify v1.7.0版本进行自测试并验证通过：

1. MCP服务对接验证

2. MCP工具在AI Agent模式下调用能力测试

3. MCP工具在AI Chatflow模式下调用能力测试

其中，MCP配置为：

{
  "mindoc": {
    "transport": "streamable_http",
    "url": "http://10.0.10.104:8181/mcp/?api_key=demo-mcp-api-key",
    "headers":{},
    "timeout":600
  }
}

对应的app.conf配置为：

# MCP Server 功能
enable_mcp_server="${MINDOC_ENABLE_MCP_SERVER||true}"
mcp_api_key="${MINDOC_MCP_API_KEY||demo-mcp-api-key}"

[Copilot]

Pull Request Overview

This PR adds MCP (Model Context Protocol) Server functionality to MinDoc, enabling global document search capabilities. The implementation provides a streamable HTTP server that exposes document search tools for AI agents to query MinDoc's content repository.

Key changes:

• New MCP server package with authentication middleware and global search tools
• HTTP routing and filtering integration for MCP endpoints
• Go version upgrade from 1.18 to 1.23 to support mcp-go dependency

Reviewed Changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
routers/router.go	Adds MCP server routing with conditional enablement
routers/filter.go	Integrates MCP authentication middleware into request filtering
mcp/middleware.go	Implements API key authentication for MCP requests
mcp/mcp.go	Core MCP server setup and tool registration
mcp/handler.go	Global search tool implementation and request handling
go.mod	Updates Go version to 1.23 and adds mcp-go dependency
conf/app.conf.example	Adds MCP server configuration options
commands/daemon/daemon.go	Minor import formatting adjustment

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[Copilot]

Type assertion assumes pageIndex is an int, but the tool definition uses mcp.WithNumber which may provide a float64. This could cause the assertion to fail and default to 0. Use type assertion to float64 and convert to int, or handle the conversion properly.

Suggested change

	pageIndex, _ := paramMap["pageIndex"].(int)
	pageIndex := 1
	if v, ok := paramMap["pageIndex"].(float64); ok {
	pageIndex = int(v)
	}

[Copilot]

Pull Request Overview

Copilot reviewed 8 out of 9 changed files in this pull request and generated 2 comments.

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