#20335: docs: add AgentFlow to Built with OpenClaw section

## AgentFlow — Visual AI Agent Organization Designer Adds AgentFlow to a new "Built with OpenClaw" section in the README. **What is AgentFlow?** - Visual drag-and-drop org chart editor for AI agent teams - Exports OpenClaw-compatible YAML configs - Built with Next.js, React Flow, and Supabase - MIT licensed 🔗 **Live:** https://agentflow.frexida.com 📦 **Repo:** https://github.com/Frexida/agentflow Built entirely by an AI agent team running on OpenClaw. 🦞 <!-- greptile_comment --> <h3>Greptile Summary</h3> Adds a new "Built with OpenClaw" community showcase section to the README, featuring AgentFlow — a visual drag-and-drop org chart editor that exports OpenClaw-compatible YAML configs. - New `## Built with OpenClaw` section added between "Email hooks (Gmail)" and "Molty" sections - Single entry links to both the [live site](https://agentflow.frexida.com) and [GitHub repo](https://github.com/Frexida/agentflow) - Documentation-only change with no code impact <h3>Confidence Score: 5/5</h3> - This PR is safe to merge — it only adds 4 lines of markdown to the README with no code changes. - Documentation-only change that adds a community project link to the README. No code, configuration, or dependency changes. The markdown is well-formatted and consistent with the existing README style. - No files require special attention. _{Last reviewed commit: 082f17a} <!-- greptile_other_comments_section --> _{(2/5) Greptile learns from your feedback when you react with thumbs up/down!} <!-- /greptile_comment -->