Add chamnan to Development & Code Tools

Repository-local engineering context for Claude Code: an architecture index, an
impact map, session records, and the decisions behind them, committed as
markdown beside the code.

README.md

@@ -120,6 +120,7 @@ Skills are not MCP servers and not tools. MCP defines how an agent connects to e
 - [artifacts-builder](https://github.com/anthropics/skills/tree/main/skills/web-artifacts-builder) - Suite of tools for creating elaborate, multi-component claude.ai HTML artifacts using modern frontend web technologies (React, Tailwind CSS, shadcn/ui).
 - [aws-skills](https://github.com/zxkane/aws-skills) - AWS development with CDK best practices, cost optimization MCP servers, and serverless/event-driven architecture patterns.
 - [building-blog](https://github.com/BuildShipGrowRepeat/nextjs-sanity-blog-skill) - Adds an SEO-first, i18n-ready blog to a Next.js + Sanity site via a 40-question intake, a one-page plan, and a 20-section spec. Includes a generator for AI hero images via Gemini 3 Pro Image (Nano Banana Pro). *By [@BuildShipGrowRepeat](https://github.com/BuildShipGrowRepeat)*
+- [chamnan](https://github.com/ArcticFox2029/chamnan) - Keeps a repository's engineering context beside the code as committed markdown — an architecture index, an impact map, session records, and the decisions behind them — so a session reads instead of rediscovering. Repository-local, no network, Python stdlib only. On a polyglot test corpus, 11.5M tokens of source become a 52k-token index, of which roughly 3k reach each session. *By [@ArcticFox2029](https://github.com/ArcticFox2029)*
 - [Changelog Generator](./changelog-generator/) - Automatically creates user-facing changelogs from git commits by analyzing history and transforming technical commits into customer-friendly release notes.
 - [Chrome Relay](https://chrome-relay.kushalsm.com/) - Drives the user's already-open Chrome session — cookies, SSO, extensions, localhost — through a local CLI bridge. Real-Chrome counterpart to Playwright Browser Automation; install via `npx skills add chrome-relay` + a [Chrome Web Store extension](https://chromewebstore.google.com/detail/chrome-relay/cpdiapbifblhlcpnmlmfpgfjlacebokb). No remote relay, no Playwright fixtures, no MCP server needed.
 - [Claude Code Terminal Title](https://github.com/bluzername/claude-code-terminal-title) - Gives each Claud-Code terminal window a dynamic title that describes the work being done so you don't lose track of what window is doing what.