feat: add line server

[SokiKawashima]

Description

Addition of new MCP server implementation for LINE Bot integration

Server Details

• Server: line

Motivation and Context

Implementation of MCP protocol support for LINE, Japan's leading messaging platform. This addition will facilitate LLM application development targeting the Japanese market and enable seamless integration with LINE's messaging ecosystem.

How Has This Been Tested?

The following End-to-End tests were conducted to verify all functionalities:

1. Profile Information Retrieval

• Test Content: Profile information retrieval using user ID
• Method: Using line_get_profile tool
• Result: Successfully confirmed profile information retrieval
• Prerequisites: None

2. Message Sending Functionality

• Test Content: Message sending from LINE Bot to users
• Method: Using line_send_message tool
• Result: Successfully confirmed message delivery to specified users
• Prerequisites:
  • LINE Channel Access Token configuration required
  • Configuration needed in claude_desktop_config.json:

    "line": {
    "command": "node",
    "args": [
    "/Users/kawashimasoki/dev/mcp/line/build/index.js"
    ],
    "env": {
    "LINE_CHANNEL_ACCESS_TOKEN": "your_access_token"
    }
    }

Breaking Changes

No breaking changes.

Types of changes

• [x] New MCP Server
• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Documentation update

Checklist

• [x] I have read the MCP Protocol Documentation
• [x] My server follows MCP security best practices
• [x] I have updated the server's README accordingly
• [x] I have tested this with an LLM client
• [x] My code follows the repository's style guidelines
• [x] New and existing tests pass locally
• [x] I have added appropriate error handling
• [x] I have documented all environment variables and configuration options

Additional context

• Implementation details for LINE Messaging API integration
• Required environment variables (LINE Channel Secret, Channel Access Token)
• Error handling strategies and policies
• Security considerations for LINE platform integration
• Documentation for LINE-specific configuration requirements