docs(mcp): add a README button for one-click add to Cursor

Author: stainless-app[bot]

packages/mcp-server/README.md

@@ -49,6 +49,13 @@ For clients with a configuration JSON, it might look something like this:
 }
 ```
 
+### Cursor
+
+      If you use Cursor, you can install the MCP server by using the button below. You will need to set your environment variables
+      in Cursor's `mcp.json`, which can be found in Cursor Settings > Tools & MCP > New MCP Server.
+
+      [![Add to Cursor](https://cursor.com/deeplink/mcp-install-dark.svg)](https://cursor.com/en-US/install-mcp?name=@stainless-api/sdk-mcp&config=eyJjb21tYW5kIjoibnB4IiwiYXJncyI6WyIteSIsIkBzdGFpbmxlc3MtYXBpL3Nkay1tY3AiXSwiZW52Ijp7IlNUQUlOTEVTU19BUElfS0VZIjoiU2V0IHlvdXIgU1RBSU5MRVNTX0FQSV9LRVkgaGVyZS4iLCJTVEFJTkxFU1NfUFJPSkVDVCI6IlNldCB5b3VyIFNUQUlOTEVTU19QUk9KRUNUIGhlcmUuIn19)
+
 ## Exposing endpoints to your MCP Client
 
 There are two ways to expose endpoints as tools in the MCP server: