DESIGN.md joins the persistence gate

With the PRODUCT.md skip fixed, the Opus smoke unmasked the adjacent
gap: the model builds a new world and never writes DESIGN.md (zero
attempts), so the worker's requiresDesign assertion correctly fails the
run. Same disease, same treatment: DESIGN.md is now part of recording
the decision, written before the first build edit in the same stretch
as the direction contract, and the finishing reviewer checks
persistence first, before any craft point is scored.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

skill/reference/new-work.md

@@ -68,7 +68,7 @@ Your measured rendition prior: warm, bookish, family, and child-facing subjects
 
 Before code, state the chosen direction as a contract in the artifact's opening comment, five short blocks, 150 words at most. THESIS: the one idea this surface owns and the category-default arrangement it refuses. OWN-WORLD: the palette and component language, specific enough to be recognizable with all content removed. STORY: what the visitor understands, believes, and does. FIRST VIEWPORT: the exact composition, what is where and at what scale, and where the primary action sits. FORM: the chosen form, its position on your ordered list, and the seed key the script printed. If a block reads like a mood, the direction is not decided yet; the finishing review audits the render against this contract. <!-- rule:skill-decide-then-build -->
 
-When a new or replacement world is chosen, write DESIGN.md at the appropriate project or app boundary using [document.md](document.md). Record only durable system rules; exact tokens may remain provisional until the first build establishes them. An ordinary extension does not rewrite DESIGN.md.
+When a new or replacement world is chosen, DESIGN.md is part of recording the decision, not an aftercare step: write it at the appropriate project or app boundary using [document.md](document.md) before the first build edit lands, in the same working stretch as the direction contract. Record only durable system rules; exact tokens may remain provisional until the first build establishes them, and you update the file when the build settles them. A new world shipped with no DESIGN.md is an incomplete run, exactly as a missing PRODUCT.md is; the finishing review checks the file exists and matches the built world. An ordinary extension does not rewrite DESIGN.md. <!-- rule:skill-design-md-before-build -->
 
 If the work establishes durable strategy for a route or artifact, read its existing surface brief, then update it:
 
@@ -101,4 +101,4 @@ Preserve semantics, accessibility, performance, responsiveness, project conventi
 
 Inspect desktop and mobile, critique the render against the user's request, the direction contract, and DESIGN.md, fix material gaps, and re-inspect. On a Persuade surface, verify the mode did its job: a first-time visitor should know what this is, why it matters, and what to do within seconds, in the form's own vocabulary. After a first implementation of a new world, update DESIGN.md with the exact tokens and behaviors that survived the build.
 
-When the harness can run a separate agent, this review belongs there, not in the build thread: give it the original request, confirmed answers, the artifact path, its direction contract, DESIGN.md, and existing hook findings. Ask for a short list of material fixes, promise by promise against the contract, apply them, and finish. Do not run a second detector. <!-- rule:skill-finish-separate-reviewer -->
+When the harness can run a separate agent, this review belongs there, not in the build thread: give it the original request, confirmed answers, the artifact path, its direction contract, DESIGN.md, and existing hook findings. The reviewer's first check is persistence: on a new or replacement world, PRODUCT.md and DESIGN.md exist and DESIGN.md matches the built world; a missing file fails the review before any craft point is scored. Then ask for a short list of material fixes, promise by promise against the contract, apply them, and finish. Do not run a second detector. <!-- rule:skill-finish-separate-reviewer -->