docs(mcp): update copy for "Add Custom MCP" button

Author: brandonmcconnell

docs/snippets/shared/guides/mcp-server-setup.mdx

@@ -18,7 +18,7 @@ Powered by 🪄 [Tadata](https://tadata.com) - The platform for instantly buildi
     ### Open MCP Settings in Cursor
     1. Press `Shift+Command+J` (Mac) or `Shift+Ctrl+J` (Windows/Linux) to open Cursor's settings.
     2. Look for "MCP Tools" in the left sidebar categories.
-    3. Click "+ New MCP Server".
+    3. Click "Add Custom MCP".
     This will open the mcp.json file in the editor, which you need to edit.
   </Step>
   <Step>