docs: add nanoclaw.dev link to README header

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -7,6 +7,7 @@
 </p>
 
 <p align="center">
+  <a href="https://nanoclaw.dev">nanoclaw.dev</a>&nbsp; • &nbsp;
   <a href="README_zh.md">中文</a>&nbsp; • &nbsp;
   <a href="https://discord.gg/VDdww8qS42"><img src="https://img.shields.io/discord/1470188214710046894?label=Discord&logo=discord&v=2" alt="Discord" valign="middle"></a>&nbsp; • &nbsp;
   <a href="repo-tokens"><img src="repo-tokens/badge.svg" alt="34.9k tokens, 17% of context window" valign="middle"></a>