Add read-only Parallel web gatekeeper

[RowanAldean]

Summary

• add an optional, install-once gatekeeper-parallel package
• expose read-only Parallel web search and URL extraction through an ambient PARALLEL binding
• keep the deployment API key inside the Gatekeeper Worker and audit every returned result as an observation
• add deploy metadata, generated Worker types, setup documentation, and release-manifest coverage

Why

Parallel's Search and Extract APIs return LLM-optimized web content. Exposing them through a Gatekeeper gives Cloudflare OS agents a native web research path while preserving the capability and observation model used by the rest of the project.

Security and behavior

• PARALLEL_API_KEY is a deployment secret and is never returned to agents or Gadgets
• the gatekeeper provides no authentication identity and no write actions
• searches and extractions are released only after observation authorization
• extraction accepts only HTTP(S) URLs and enforces Parallel's 20-URL request limit

This is a draft to get feedback on the integration shape and whether this belongs as a first-party Gatekeeper package.

Validation

• pnpm types:check
• pnpm lint:check (passes with existing repository warnings)
• pnpm --filter @gadgets/gatekeeper-parallel build
• node --test scripts/release-manifest.test.js
• Wrangler deployment dry-run for gatekeeper-parallel

[github-actions]

All contributors have signed the CLA ✍️ ✅
_{Posted by the CLA Assistant Lite bot.}

[RowanAldean]

I have read the CLA Document and I hereby sign the CLA

[RowanAldean]

I know this PR is 16 files as per guidelines so will open a discussion too? This just felt useful given low cost web search capability and can work my existing setup this last couple of weeks. Happy to close in favour of discussing how to add ☺️

[RowanAldean]

Closed in favour of having my Hermes agent remind me after I use the OS more 👀