feat(idtk): add commands/new-storyboard.md (HeyGen A-Roll + Higgsfield B-Roll orchestrator) [DOJ-4756]

[lapc506]

Summary

Adds commands/new-storyboard.md — a Storyboard Agent that consumes a video-brief.md (from write-video-script.md) and emits:

• An appended ## Storyboard table to the brief
• A sidecar <stem>.storyboard.json for downstream automation

Six explicit phases (Doji's 4-phase mega-prompt + Review Gate + Quality Rules promoted to first-class phases per IDT convention — justified in Decision Rationale).

Scope

• ✅ Prompt generation only (deterministic, no external API calls)
• ✅ HeyGen A-Roll prompts (talking head, encuadre + emotional state for Avatar Clone)
• ✅ Higgsfield/Kling B-Roll prompts (Draw-to-Image with visual + motion description)
• ✅ 80/20 quality rule (B-Roll for technical concepts, A-Roll for hooks/intros/outros)
• ✅ Multi-tenant neutral (no Dojo-specific copy)
• ✅ Overlay protocol compliance (DOJ-3706/3707)
• ❌ Actual HeyGen / Higgsfield / Kling / Gemini Omni API integration — tracked separately as DOJ-4758

Linear

• Issue: DOJ-4756
• Follow-up (integration): DOJ-4758

Test plan

• `scripts/ci/check_frontmatter.py` — passes (67 valid, 2 skipped)
• `scripts/ci/check_agent_references.py` — passes (19 agents, all refs resolve)
• `scripts/ci/check_json_schemas.py` — passes (4 schemas valid)
• Multi-tenant grep returns zero hits

Created by Claude Code on behalf of @andres@dojocoding.io

🤖 Generated with Claude Code

[lapc506]

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