Revert npm registry config from Dockerfile.local (local dev uses public registry)

Dockerfile.local

@@ -1,13 +1,8 @@
 # Frontend build stage
 FROM node:20-alpine AS frontend-builder
 
-ARG NPM_REGISTRY=https://deps.global.bsf.tools/npm/
-
 WORKDIR /app/frontend
 
-# Configure npm registry if provided
-RUN if [ -n "$NPM_REGISTRY" ]; then npm config set registry "$NPM_REGISTRY"; fi
-
 # Copy package files
 COPY frontend/package*.json ./
 RUN npm install