Add prominent API key button to README

Author: joachimBrindeau

README.md

@@ -15,6 +15,12 @@ A Domain MCP server that brings natural language domain management to Claude, Cu
 
 > "List my domains" · "Register example.com" · "Set up DNS for mysite.com" · "Enable WHOIS privacy"
 
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+**🔑 Get Started:** [![Get Dynadot API Key](https://img.shields.io/badge/Get%20Dynadot%20API%20Key-blue?style=for-the-badge&logo=key)](https://www.dynadot.com/account/domain/setting/api.html?s9F6L9F7U8Q9U8Z8v)
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 ## Features
 
 - **🤖 Natural Language Domain Management**: Use AI assistants like Claude and Cursor to manage domains conversationally - no API knowledge needed