Complete screenshot-intake skill (currently a stub)

[PAMulligan]

Summary

The screenshot-intake skill (.claude/skills/screenshot-intake/SKILL.md) is marked as an incomplete stub. This is a critical Phase 1 entry point for the /build-from-screenshot pipeline.

Current State

• Process and Error Handling sections are template/reference only
• Vision analysis references "identical to canva-intake" without actual implementation guidance
• No concrete examples of build-spec.json output for screenshot sources
• Missing URL capture step details (which MCP tool to use, fallback strategies)
• No guidance on handling multi-page sites vs single screenshots

Impact

The /build-from-screenshot pipeline cannot reliably produce build-spec.json from screenshots, making this pipeline effectively broken for new users.

Acceptance Criteria

• Skill has complete, actionable process steps (not references to other skills)
• URL capture workflow documented with MCP tool selection (Chrome DevTools vs Playwright)
• Fallback strategy when MCP tools are unavailable
• Example build-spec.json output for screenshot source
• Multi-page vs single-page handling documented
• Error handling for common failures (URL unreachable, screenshot too low-res, etc.)