docs: add add-mcp install option (#122)

* docs: add add-mcp quick install option

* Update README.md

Co-authored-by: Felix Arntz <felix.arntz@vercel.com>

* Update README.md

Co-authored-by: Felix Arntz <felix.arntz@vercel.com>

---------

Co-authored-by: Felix Arntz <felix.arntz@vercel.com>

Author: andrelandgraf

README.md

@@ -13,6 +13,19 @@
 - [npm](https://www.npmjs.com/) or [pnpm](https://pnpm.io/)
 
 
+### Install with add-mcp
+
+Install the MCP server for all your coding agents:
+
+```bash
+npx add-mcp next-devtools-mcp@latest
+```
+
+Add `-y` to skip the confirmation prompt and install to all detected agents already in use in the project directory. Add `-g` to install globally across all projects.
+
+
+### Manual installation
+
 Add the following config to your MCP client:
 
 ```json