docs: add MCP config for Claude plugin + docs (ChromeDevTools#944)

Instructions tested locally.

Author: OrKoN

.mcp.json

@@ -0,0 +1,6 @@
+{
+  "chrome-devtools": {
+    "command": "npx",
+    "args": ["chrome-devtools-mcp@latest"]
+  }
+}

README.md

@@ -127,6 +127,20 @@ Chrome DevTools MCP will not start the browser instance automatically using this
 claude mcp add chrome-devtools --scope user npx chrome-devtools-mcp@latest
 ```
 
+To install Chrome DevTools MCP + skills, in Claude Code add a marketplace:
+
+```sh
+/plugin marketplace add ChromeDevTools/chrome-devtools-mcp
+```
+
+Then, install the plugin:
+
+```sh
+/plugin install chrome-devtools-mcp
+```
+
+Restart Claude Code to have the MCP server and skills load (check with `/skills`).
+
 </details>
 
 <details>