docs: install Browser Use from the Vercel Marketplace via the deploy button

[mathisdittrich]

🔗 Linked issue

Vercel Marketplace review feedback (2026-09-10): the approval checklist requires a Marketplace template as a deploy option in the product flow, and Vercel asked for a Next.js/eve template to submit to the templates gallery.

📚 Description

• The Deploy with Vercel button now carries a stores parameter for the browseruse integration / agent product (deploy-button source docs). The deploy flow installs the Browser Use integration, bills through Vercel, and sets BROWSER_USE_API_KEY on the project.
• BROWSER_USE_API_KEY is removed from the env= prompt so it is not defined twice; the README explains the manual-key path for people who already have one.
• docs/ENVIRONMENT.md mentions where the key comes from on a Marketplace deploy.

Merge condition: the browseruse listing is still public: false on Vercel's side. Until Vercel publishes it, the store step only resolves for teams that can see the listing. Merge once the listing is public, or keep it on the branch until then.

Docs-only change, no code touched.

📝 Checklist

• I have linked an issue or discussion.
• I have updated the documentation accordingly.
• npm run typecheck passes locally. (no TypeScript changes)

🤖 Generated with Claude Code

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Summary by cubic

Updates the Vercel deploy button to install Browser Use from the Vercel Marketplace, so BROWSER_USE_API_KEY is set automatically instead of prompted for. The README and docs/ENVIRONMENT.md now document the manual-key path for people who already have a key.

Rollout

• The deploy button only installs the Browser Use integration once Vercel publishes the browseruse listing; until then it resolves only for teams that can see the listing.

^{Written for commit b759180. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}