docs: add quick project summary

Author: ngallodev

README.md

@@ -3,6 +3,13 @@
 **Portfolio case study:** https://ngallodev-software.uk/projects/codebase-memory-cli  
 **Documentation:** https://ngallodev.github.io/codebase-memory-cli/
 
+## Quick summary
+
+- **What it is:** a **modified fork** of [DeusData/codebase-memory-mcp](https://github.com/DeusData/codebase-memory-mcp), not an independently originated code-intelligence system.
+- **Upstream credit:** DeusData authored the original architecture and substantial implementation, including the graph/index engine, parser pipeline, storage, daemon/watcher foundation, and broad language support.
+- **What this fork changes:** it removes the supported MCP server/integration surface and makes a local CLI/JSON interface the product boundary for environments where third-party MCP servers are prohibited.
+- **When to use it:** prefer the upstream project in ordinary environments; use this fork when policy requires the CLI-only boundary.
+
 > **Upstream attribution:** this repository is a **modified fork** of
 > [DeusData/codebase-memory-mcp](https://github.com/DeusData/codebase-memory-mcp),
 > originally authored and maintained by **DeusData**. The upstream project