feat(F-001): scaffold modular monolith skeleton with boundary checker

- TypeScript + Fastify skeleton under project/ (src/modules, shared, infrastructure, app)
- scripts/check-module-boundaries.mjs enforcing module public-API rules (tested with fixtures)
- GET /health endpoint, error envelope without stack leakage
- specs/F-001-scaffold (SPEC/DESIGN/TASKS/TESTS), spec/tech.md dependency justification
- 30-ticket MercadoDeVida roadmap in backlog/features.json, spec/roadmap.md
- All gates approved: reviewer, security, qa; verify.sh green

harness/model-routing.yml

@@ -0,0 +1,23 @@
+version: 1
+
+# Sequential role model hints for Pi. The parent session changes model before
+# each stage when a different model is desired. No parallel agents/subagents.
+roles:
+  leader:
+    model: default
+    reasoning: medium
+  architect:
+    model: strong
+    reasoning: medium
+  implementer:
+    model: default
+    reasoning: medium
+  reviewer:
+    model: strong
+    reasoning: low
+  security:
+    model: strong
+    reasoning: medium
+  qa:
+    model: default
+    reasoning: low