refactor(plan-design-review): carve review body into on-demand section

Fifth Phase B carve (v2_PLAN.md:220, bundled with plan-eng). Moves the 7 design
passes, required outputs, and review report — everything after Step 0 scope and
the mockup/rating phase — into sections/review-sections.md behind a STOP-Read.
Step 0, Step 0.5 mockups, the rating method, and EXIT_PLAN_MODE_GATE stay in the
always-loaded skeleton.

Measured: skeleton 112,057 -> 76,024 B (-32.2%). Union preserved. Atomic with
tests + all-host regen: parity sectioned (maxSkeletonBytes 82K), added to
SECTIONS_EXTRACTED, gen-skill-docs reads the union. Layer 0 green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

test/gen-skill-docs.test.ts

@@ -745,7 +745,7 @@ describe('REVIEW_DASHBOARD resolver', () => {
   });
 
   test('plan-design-review chaining mentions eng, ceo, and design skills', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('/plan-eng-review');
     expect(content).toContain('/plan-ceo-review');
     expect(content).toContain('/design-shotgun');
@@ -1551,7 +1551,7 @@ describe('preamble routing injection', () => {
 
 describe('DESIGN_OUTSIDE_VOICES resolver', () => {
   test('plan-design-review contains outside voices section', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('Design Outside Voices');
     expect(content).toContain('CODEX_AVAILABLE');
     expect(content).toContain('LITMUS SCORECARD');
@@ -1570,7 +1570,7 @@ describe('DESIGN_OUTSIDE_VOICES resolver', () => {
   });
 
   test('branches correctly per skillName — different prompts', () => {
-    const planContent = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const planContent = readSkillUnion('plan-design-review');
     const consultContent = fs.readFileSync(path.join(ROOT, 'design-consultation', 'SKILL.md'), 'utf-8');
     // plan-design-review uses analytical prompt (high reasoning)
     expect(planContent).toContain('model_reasoning_effort="high"');
@@ -1583,7 +1583,7 @@ describe('DESIGN_OUTSIDE_VOICES resolver', () => {
 
 describe('DESIGN_HARD_RULES resolver', () => {
   test('plan-design-review Pass 4 contains hard rules', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('Design Hard Rules');
     expect(content).toContain('Classifier');
     expect(content).toContain('MARKETING/LANDING PAGE');
@@ -1596,26 +1596,26 @@ describe('DESIGN_HARD_RULES resolver', () => {
   });
 
   test('includes all 3 rule sets', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('Landing page rules');
     expect(content).toContain('App UI rules');
     expect(content).toContain('Universal rules');
   });
 
   test('references shared AI slop blacklist items', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('3-column feature grid');
     expect(content).toContain('Purple/violet/indigo');
   });
 
   test('includes OpenAI hard rejection criteria', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('Generic SaaS card grid');
     expect(content).toContain('Carousel with no narrative purpose');
   });
 
   test('includes OpenAI litmus checks', () => {
-    const content = fs.readFileSync(path.join(ROOT, 'plan-design-review', 'SKILL.md'), 'utf-8');
+    const content = readSkillUnion('plan-design-review');
     expect(content).toContain('Brand/product unmistakable');
     expect(content).toContain('premium with all decorative shadows removed');
   });

test/helpers/parity-harness.ts

@@ -263,7 +263,13 @@ export const PARITY_INVARIANTS: ParityInvariant[] = [
     minBytes: 70_000,
   },
   {
+    // Carved (v2 plan T9): skeleton + sections/review-sections.md. The 7 design
+    // passes + required outputs moved to the section; content checks run against
+    // the union. Skeleton shrank 112,057 -> 76,024 B (-32.2%); maxSkeletonBytes
+    // 82KB = measured + headroom.
     skill: 'plan-design-review',
+    sectioned: true,
+    maxSkeletonBytes: 82_000,
     mustContain: [
       'design',
       'visual',

test/skill-size-budget.test.ts

@@ -163,7 +163,7 @@ describe('SKILL.md size budget regression (gate, free)', () => {
     // because prose moved into sections/*.md. The union size is guarded instead
     // by the sectioned ship invariant in parity-harness.ts (minBytes on the
     // skeleton+sections union), so exempt the skeleton from the body-strip floor.
-    const SECTIONS_EXTRACTED = new Set<string>(['ship', 'plan-ceo-review', 'office-hours', 'plan-eng-review']);
+    const SECTIONS_EXTRACTED = new Set<string>(['ship', 'plan-ceo-review', 'office-hours', 'plan-eng-review', 'plan-design-review']);
 
     const undershoots: Array<{
       skill: string; beforeBytes: number; afterBytes: number; ratio: number;