Add Satoshi API community example

[Bortlesboat]

Summary

• add a community Satoshi API + Browserbase Stagehand example
• fetch the free Satoshi API /api/v1/fees/recommended endpoint before opening a Browserbase session
• document the optional x402 paid /api/v1/fees/now route and include the nested community package in the pnpm workspace
• related listing path: companion Browserbase templates PR Add Satoshi API fee agent template templates#97

Reviewer Packet

• public packet: https://gist.github.com/Bortlesboat/41f694ec0d1bb6f01940305d004066b5
• integration intro draft: https://gist.github.com/Bortlesboat/41f694ec0d1bb6f01940305d004066b5#file-introduction-md
• quickstart draft: https://gist.github.com/Bortlesboat/41f694ec0d1bb6f01940305d004066b5#file-quickstart-md
• TypeScript example: https://gist.github.com/Bortlesboat/41f694ec0d1bb6f01940305d004066b5#file-index-ts
• optional Browse.sh skill draft: https://gist.github.com/Bortlesboat/41f694ec0d1bb6f01940305d004066b5#file-browse-sh-skill-md

Verification

• corepack pnpm --filter browserbase-satoshi-api-example typecheck
• corepack pnpm exec eslint examples/community/satoshi-api/src/index.ts
• corepack pnpm exec prettier --check examples/community/README.md examples/community/satoshi-api/README.md examples/community/satoshi-api/package.json examples/community/satoshi-api/src/index.ts examples/community/satoshi-api/tsconfig.json pnpm-workspace.yaml
• curl.exe -i https://bitcoinsapi.com/api/v1/fees/recommended returned HTTP 200

Notes

Repo-wide checks appear red on main before this change: prettier reports existing formatting warnings across many files, and eslint crashes in the existing vercel-puppeteer example because @eslint/eslintrc is missing.