docs: add OpenCode integration instructions

[pascalandy]

Summary

This PR adds integration instructions for OpenCode, an open-source AI coding agent, to the README.md.

Details

OpenCode supports MCP servers through its configuration file (opencode.json or global config.json). Adding these instructions helps OpenCode users quickly set up and use the Chrome DevTools MCP features within their agent sessions.

The instructions follow the alphabetical order of the existing client list (inserted between Kiro and Qoder).

[google-cla]

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[pascalandy]

Stucked here :-( The doc does not follow the console.

Add an alternate email address
Open your Google Account.
You might need to sign in.
Click Personal info.
Click Email.
Next to "Alternate emails," click Add alternate email.
You may need to sign in again.
If you use an account from your work or school, you might not find this option. Ask your administrator for help.

[527bcyxhtg-web]

ok

[OrKoN]

It looks like OpenCode is already on the list