Add "oatpp-mcp" C++ implementation to community servers section

Add "oatpp-mcp" C++ implementation to community servers section

Author: lganzzzo

README.md

@@ -76,6 +76,7 @@ A growing set of community-developed and maintained servers demonstrates various
 - **[Pandoc](https://github.com/vivekVells/mcp-pandoc)** - MCP server for seamless document format conversion using Pandoc, supporting Markdown, HTML, and plain text, with other formats like PDF, csv and docx in development. 
 - **[HuggingFace Spaces](https://github.com/evalstate/mcp-hfspace)** - Server for using HuggingFace Spaces, supporting Open Source Image, Audio, Text Models and more. Claude Desktop mode for easy integration.
 - **[ChatSum](https://github.com/mcpso/mcp-server-chatsum)** - Query and Summarize chat messages with LLM. by [mcpso](https://mcp.so)
+- **[oatpp-mcp](https://github.com/oatpp/oatpp-mcp)** - C++ MCP integration for Oat++. Use [Oat++](https://oatpp.io) to build MCP servers.
 
 ## 📚 Resources