Story 26: Establish TDD workflow and quality gates

Add workflow engine with acceptance gates, test recording, and review
queue. Frontend displays gate status (blocked/ready), test summaries,
failing badges, and warnings. Proceed action is disabled when gates
are not met. Includes 13 unit tests (Vitest) and 9 E2E tests
(Playwright) covering all five acceptance criteria.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/tsconfig.json

@@ -20,6 +20,5 @@
     "noUnusedParameters": true,
     "noFallthroughCasesInSwitch": true
   },
-  "include": ["src"],
-  "references": [{ "path": "./tsconfig.node.json" }]
+  "include": ["src"]
 }