feat: sync Draft-First PRD and design handoff

[mrcha033]

What changed

• sync show-me-the-prd-codex to v0.10.0
• replace the 5–6 response serial interview with a three-response Draft-First flow
• add an explicit assumption ledger and draft confirmation step
• add UI-gated design reference discovery, visual screening, local storage, attribution, and copyright guards
• sync goaljaby-codex to v0.6.0 and carry PRD design references into PLAN/VALIDATION without consuming the goal-command budget

Codex adaptation

The upstream AskUserQuestion workflow is expressed through the existing Codex §A numbered-question contract. Backend/CLI/library work bypasses the design gate; direct user URLs are recorded rather than re-collected.

Validation

• manifest/version assertions
• Draft-First, Turn 2.5, assumption-ledger, source-schema, and design-handoff contract assertions
• git diff --check