Add Paubox MCP server to README (#2535)

Author: ralph-tice

README.md

@@ -323,6 +323,7 @@ Official integrations are maintained by companies building production ready MCP
 - <img height="12" width="12" src="https://paiml.com/favicon.ico" alt="PAIML Logo" /> **[PAIML MCP Agent Toolkit](https://github.com/paiml/paiml-mcp-agent-toolkit)** - Professional project scaffolding toolkit with zero-configuration AI context generation, template generation for Rust/Deno/Python projects, and hybrid neuro-symbolic code analysis.
 - <img height="12" width="12" src="https://app.paperinvest.io/favicon.svg" alt="Paper Logo" /> **[Paper](https://github.com/paperinvest/mcp-server)** - Realistic paper trading platform with market simulation, 22 broker emulations, and professional tools for risk-free trading practice. First trading platform with MCP integration.
 - **[Patronus AI](https://github.com/patronus-ai/patronus-mcp-server)** - Test, evaluate, and optimize AI agents and RAG apps
+- <img height="12" width="12" src="https://mcp.paubox.com/paubox.png" alt="Paubox Logo" />**[Paubox](https://mcp.paubox.com)** - Official MCP server which allows AI agents to interact with Paubox Email API. HITRUST certified.
 - <img height="12" width="12" src="https://www.paypalobjects.com/webstatic/icon/favicon.ico" alt="PayPal Logo" /> **[PayPal](https://mcp.paypal.com)** - PayPal's official MCP server.
 - <img height="12" width="12" src="https://ww2-secure.pearl.com/static/pearl/pearl-logo.svg" alt="Pearl Logo" /> **[Pearl](https://github.com/Pearl-com/pearl_mcp_server)** - Official MCP Server to interact with Pearl API. Connect your AI Agents with 12,000+ certified experts instantly.
 - <img height="12" width="12" src="https://www.perplexity.ai/favicon.ico" alt="Perplexity Logo" /> **[Perplexity](https://github.com/ppl-ai/modelcontextprotocol)** - An MCP server that connects to Perplexity's Sonar API, enabling real-time web-wide research in conversational AI.