Add backend policy tests and API client split

Dockerfile

@@ -17,15 +17,17 @@ WORKDIR /app
 
 ENV NODE_ENV=production
 
-# Copy backend package.json as main package.json
-COPY backend/package.json ./package.json
+# Copy backend package metadata as runtime package metadata
+COPY backend/package.json backend/package-lock.json ./
 
 # Install dependencies
-RUN npm install --omit=dev
+RUN npm ci --omit=dev
 
 # Copy backend source directly into root
 COPY backend/index.js ./index.js
 COPY backend/db.js ./db.js
+COPY backend/policies ./policies
+COPY backend/utils ./utils
 
 # Copy built frontend
 COPY --from=builder /app/dist ./dist