Add Things3 MCP server to official integrations list

- Added Things3 MCP server for comprehensive Things3 task management integration on macOS
- Positioned alphabetically between Thirdweb and Tianji
- Provides 25 specialized tools for TODOs, projects, areas, tags, and bulk operations

Author: urbanogardun

README.md

@@ -531,6 +531,7 @@ A growing set of community-developed and maintained servers demonstrates various
 - **[Tavily search](https://github.com/RamXX/mcp-tavily)** - An MCP server for Tavily's search & news API, with explicit site inclusions/exclusions
 - **[Telegram](https://github.com/chigwell/telegram-mcp)** - An MCP server that provides paginated chat reading, message retrieval, and message sending capabilities for Telegram through Telethon integration.
 - **[Telegram-Client](https://github.com/chaindead/telegram-mcp)** - A Telegram API bridge that manages user data, dialogs, messages, drafts, read status, and more for seamless interactions.
+- **[Things3 MCP](https://github.com/urbanogardun/things3-mcp)** - Things3 task management integration for macOS with comprehensive TODO, project, and tag management.
 - **[Teradata](https://github.com/arturborycki/mcp-teradata)** - his MCP server enables LLMs to interact with Teradata databases. This MCP Server support tools and prompts for multi task data analytics
 - **[Terminal-Control](https://github.com/GongRzhe/terminal-controller-mcp)** - A MCP server that enables secure terminal command execution, directory navigation, and file system operations through a standardized interface.
 - **[TFT-Match-Analyzer](https://github.com/GeLi2001/tft-mcp-server)** - MCP server for teamfight tactics match history & match details fetching, providing user the detailed context for every match.