Taxonomy 1.15.0: payments/adyen (#14)

[SulimanAbdulrazzaq]

What does this PR do, and why does it fit the north star?

Adds payments/adyen to the closed skill taxonomy and advances its version from 1.14.0 to 1.15.0.

Adyen is an established payment provider whose official @adyen/api-library SDK cannot currently be represented by the closed vocabulary. Adding the slug first allows a separate Tier 1 package-map PR to detect that unambiguous SDK import without weakening the taxonomy boundary.

This is part one of the two-PR process agreed in #14. No detection map changes are included here.

Checklist

• Tests pass locally (npm test) — focused affected suites pass; the complete suite was previously limited by Windows Git-fixture timing
• npm run typecheck passes

If this touches WHAT data leaves the machine, or WHERE it's sent

• Links the prior discussion issue: Add payment-provider signatures: Square, Braintree, Razorpay, Adyen (pick one) #14
• Taxonomy version bumped
• Closed-vocabulary privacy tests pass

Docs and changelog

• CHANGELOG.md entry added under [Unreleased]
• No additional documentation is required for this prerequisite

Additional context

The branch is updated with current upstream main, preserving the upstream Okta detection entry while retaining the Adyen taxonomy addition. The final PR diff remains limited to taxonomy.json and CHANGELOG.md.

Validation after updating from upstream:

• package-map, skill-detect, and taxonomy contract tests: 133 passed
• structural-signal.test.ts and private-label.test.ts with 30-second test/hook timeouts: 12 passed
• npm run typecheck: passed
• npm run build: passed
• git diff --check: passed

The earlier Windows Node 20 failures were timeouts/Windows temporary-directory locking in unrelated privacy fixtures. The exact base SHA passes Windows Node 20. Fresh CI on the conflict-free branch passes all seven jobs, including Windows Node 20.

The follow-up package-map entry for @adyen/api-library remains blocked until this taxonomy slug is merged.

[jpbelmo]

Pushed the 1.16.0 bump and the CHANGELOG merge to your branch (you'd anticipated exactly this in the PR description, and we're cutting a release today so I didn't want to wake you for it). Content untouched. Merging on green CI.