Add simplemem server project to README

Add simplemem to the README. This is a very simple memory system that supports semantic search, and semantic back-links. It is designed primarily for coding agents.

README.md

@@ -760,6 +760,7 @@ Persistent memory storage using knowledge graph structures. Enables AI models to
 - [graphlit-mcp-server](https://github.com/graphlit/graphlit-mcp-server) 📇 ☁️ - Ingest anything from Slack, Discord, websites, Google Drive, Linear or GitHub into a Graphlit project - and then search and retrieve relevant knowledge within an MCP client like Cursor, Windsurf or Cline.
 - [hannesrudolph/mcp-ragdocs](https://github.com/hannesrudolph/mcp-ragdocs) 🐍 🏠 - An MCP server implementation that provides tools for retrieving and processing documentation through vector search, enabling AI assistants to augment their responses with relevant documentation context
 - [jinzcdev/markmap-mcp-server](https://github.com/jinzcdev/markmap-mcp-server) 📇 🏠 - An MCP server built on [markmap](https://github.com/markmap/markmap) that converts **Markdown** to interactive **mind maps**. Supports multi-format exports (PNG/JPG/SVG), live browser preview, one-click Markdown copy, and dynamic visualization features.
+- [jcdickinson/simplemem](https://github.com/jcdickinson/simplemem) 🏎️ ☁️ 🐧 - A simple memory tool for coding agents using DuckDB and VoyageAI.
 - [kaliaboi/mcp-zotero](https://github.com/kaliaboi/mcp-zotero) 📇 ☁️ - A connector for LLMs to work with collections and sources on your Zotero Cloud
 - [mem0ai/mem0-mcp](https://github.com/mem0ai/mem0-mcp) 🐍 🏠 - A Model Context Protocol server for Mem0 that helps manage coding preferences and patterns, providing tools for storing, retrieving and semantically handling code implementations, best practices and technical documentation in IDEs like Cursor and Windsurf
 - [modelcontextprotocol/server-memory](https://github.com/modelcontextprotocol/servers/tree/main/src/memory) 📇 🏠 - Knowledge graph-based persistent memory system for maintaining context