skill: package google-gemini/gemini-skills into dockyard

[JAORMX]

Package agent skills from google-gemini/gemini-skills into the Dockyard registry.

Source

• Repo: https://github.com/google-gemini/gemini-skills
• License: Apache-2.0
• Upstream HEAD (at survey time): 5b655a4 (2026-04)
• Skill count upstream: 4
• Trust signal: Official Google Gemini org, 3.2k stars. Complements existing Dockyard claude-api skill.

Candidate skills

• gemini-api-dev
• gemini-interactions-api
• gemini-live-api-dev
• vertex-ai-api-dev

Exact paths to confirm at packaging time.

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 Gemini skills (branch skills/gemini)

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