merge: integrate test-fail-ownership into test-coverage-catalog

Combines two complementary test infrastructure features:
- Coverage audit (proactive: "what's untested?") from test-coverage-catalog
- Failure triage (reactive: "whose bug is this?") from test-fail-ownership

Resolved 3 conflicts: CHANGELOG.md (merged entries), gen-skill-docs.ts
RESOLVERS (kept all 4 entries), touchfiles.ts (merged both dependency sets).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

test/gen-skill-docs.test.ts

@@ -691,11 +691,11 @@ describe('Codex generation (--host codex)', () => {
   test('Codex review step stripped from Codex-host ship and review', () => {
     const shipContent = fs.readFileSync(path.join(AGENTS_DIR, 'gstack-ship', 'SKILL.md'), 'utf-8');
     expect(shipContent).not.toContain('codex review --base');
-    expect(shipContent).not.toContain('Investigate and fix');
+    expect(shipContent).not.toContain('CODEX_REVIEWS');
 
     const reviewContent = fs.readFileSync(path.join(AGENTS_DIR, 'gstack-review', 'SKILL.md'), 'utf-8');
     expect(reviewContent).not.toContain('codex review --base');
-    expect(reviewContent).not.toContain('Investigate and fix');
+    expect(reviewContent).not.toContain('CODEX_REVIEWS');
   });
 
   test('--host codex --dry-run freshness', () => {

test/helpers/touchfiles.ts

@@ -68,7 +68,7 @@ export const E2E_TOUCHFILES: Record<string, string[]> = {
   'plan-eng-review-artifact':  ['plan-eng-review/**'],
 
   // Ship
-  'ship-base-branch': ['ship/**'],
+  'ship-base-branch': ['ship/**', 'bin/gstack-repo-mode'],
 
   // Retro
   'retro':             ['retro/**'],
@@ -91,8 +91,8 @@ export const E2E_TOUCHFILES: Record<string, string[]> = {
   // QA bootstrap
   'qa-bootstrap': ['qa/**', 'browse/src/**', 'ship/**'],
 
-  // Coverage audit (shared fixture)
-  'ship-coverage-audit': ['ship/**', 'test/fixtures/coverage-audit-fixture.ts'],
+  // Coverage audit (shared fixture) + triage
+  'ship-coverage-audit': ['ship/**', 'test/fixtures/coverage-audit-fixture.ts', 'bin/gstack-repo-mode'],
   'review-coverage-audit': ['review/**', 'test/fixtures/coverage-audit-fixture.ts'],
 
   // Design

test/skill-validation.test.ts

@@ -1280,12 +1280,12 @@ describe('Codex skill', () => {
   test('codex-host ship/review do NOT contain codex review step', () => {
     const shipContent = fs.readFileSync(path.join(ROOT, '.agents', 'skills', 'gstack-ship', 'SKILL.md'), 'utf-8');
     expect(shipContent).not.toContain('codex review --base');
-    expect(shipContent).not.toContain('Investigate and fix');
+    expect(shipContent).not.toContain('CODEX_REVIEWS');
 
     const reviewContent = fs.readFileSync(path.join(ROOT, '.agents', 'skills', 'gstack-review', 'SKILL.md'), 'utf-8');
     expect(reviewContent).not.toContain('codex review --base');
     expect(reviewContent).not.toContain('codex_reviews');
-    expect(reviewContent).not.toContain('Investigate and fix');
+    expect(reviewContent).not.toContain('CODEX_REVIEWS');
   });
 
   test('codex integration in /plan-eng-review offers plan critique', () => {
@@ -1411,3 +1411,58 @@ describe('Codex skill validation', () => {
     }
   });
 });
+
+// --- Repo mode and test failure triage validation ---
+
+describe('Repo mode preamble validation', () => {
+  test('generated SKILL.md preamble contains REPO_MODE output', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'SKILL.md'), 'utf-8');
+    expect(content).toContain('REPO_MODE:');
+    expect(content).toContain('gstack-repo-mode');
+  });
+
+  test('generated SKILL.md contains See Something Say Something section', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'SKILL.md'), 'utf-8');
+    expect(content).toContain('See Something, Say Something');
+    expect(content).toContain('REPO_MODE');
+    expect(content).toContain('solo');
+    expect(content).toContain('collaborative');
+  });
+});
+
+describe('Test failure triage in ship skill', () => {
+  test('ship/SKILL.md contains Test Failure Ownership Triage', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('Test Failure Ownership Triage');
+  });
+
+  test('ship/SKILL.md triage uses git diff for classification', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('git diff origin/<base>...HEAD --name-only');
+  });
+
+  test('ship/SKILL.md triage has solo and collaborative paths', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('REPO_MODE');
+    expect(content).toContain('solo');
+    expect(content).toContain('collaborative');
+    expect(content).toContain('Investigate and fix now');
+    expect(content).toContain('Add as P0 TODO');
+  });
+
+  test('ship/SKILL.md triage has GitHub issue assignment for collaborative mode', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('gh issue create');
+    expect(content).toContain('--assignee');
+  });
+
+  test('{{TEST_FAILURE_TRIAGE}} placeholder is fully resolved in ship/SKILL.md', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).not.toContain('{{TEST_FAILURE_TRIAGE}}');
+  });
+
+  test('ship/SKILL.md uses in-branch language for stop condition', () => {
+    const content = fs.readFileSync(path.join(ROOT, 'ship', 'SKILL.md'), 'utf-8');
+    expect(content).toContain('In-branch test failures');
+  });
+});