skill: package stripe/agent-toolkit skills into dockyard

[JAORMX]

Package agent skills from stripe/agent-toolkit (the skills/ subtree) into the Dockyard registry.

Source

• Repo: https://github.com/stripe/agent-toolkit
• License: MIT
• Upstream HEAD (at survey time): dd6deb0 (2026-04-17)
• Skill count upstream: 3 (only skills/ subtree)
• Trust signal: Official Stripe; 1.5k stars

Candidate skills

• skills/stripe-best-practices
• skills/stripe-projects
• skills/upgrade-stripe

Acceptance criteria

• One spec.yaml per skill under skills/<name>/
• spec.ref pinned to an audited upstream commit SHA
• task validate-skill passes for each
• task scan-skill findings triaged
• Single PR grouping all Stripe skills (branch skills/stripe)

Part of the vendor-by-vendor sweep following #466 (Trail of Bits).