refactor(data): establish API contract guardrails

.gitea/workflows/ci.yml

@@ -29,5 +29,21 @@ jobs:
       - name: Run quality checks
         run: pnpm quality
 
+      - name: Check Python backend API surface
+        env:
+          BACKEND_OPENAPI_SOURCE: ${{ secrets.BACKEND_OPENAPI_SOURCE }}
+        run: |
+          if [ -z "$BACKEND_OPENAPI_SOURCE" ]; then
+            echo "BACKEND_OPENAPI_SOURCE is not configured; skipping live OpenAPI comparison."
+            exit 0
+          fi
+          pnpm contract:check
+
+      - name: Install Chromium for mobile smoke tests
+        run: pnpm exec playwright install --with-deps chromium
+
+      - name: Run critical mobile smoke tests
+        run: pnpm test:e2e:mobile-smoke
+
       - name: Enforce bundle budgets
         run: pnpm perf:bundle:check