Add air-gapped deployment option for restricted environments

Added support for air-gapped and enterprise environments where npm package access is restricted, specifically addressing esbuild platform binary download issues.

**New Files:**
- Dockerfile.frontend.prebuilt: Alternative Dockerfile that uses pre-built Angular files
- DEPLOYMENT.md: Comprehensive deployment guide with two options

**Changes:**
- package.json: Added optionalDependencies for esbuild platform binaries
  - @esbuild/darwin-arm64
  - @esbuild/darwin-x64
  - @esbuild/linux-arm64
  - @esbuild/linux-x64

**Deployment Options:**

**Option 1 - Standard Build (current default):**
- Builds Angular in Docker
- Requires npm registry access
- Best for cloud/development

**Option 2 - Pre-built (for air-gapped):**
1. Build Angular locally: npm run build:prod
2. Change dockerfile in docker-compose.yml to Dockerfile.frontend.prebuilt
3. Docker only needs to copy files, no npm required
- No npm registry access needed during Docker build
- Faster, more reliable builds
- Best for enterprise/air-gapped/CI-CD

**Troubleshooting:**
See DEPLOYMENT.md for full troubleshooting guide including:
- esbuild platform binary issues
- Custom npm registry configuration
- Environment-specific recommendations

This addresses npm package access issues in restricted environments while maintaining flexibility for standard deployments.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Dockerfile.frontend.prebuilt

@@ -0,0 +1,15 @@
+# Dockerfile for pre-built Angular frontend (air-gapped/restricted environments)
+# Build the Angular app locally first: cd frontend && npm run build:prod
+# Then use this Dockerfile to package the pre-built files
+
+FROM nginx:alpine
+
+# Copy pre-built Angular app to nginx
+COPY frontend/dist/frontend/browser /usr/share/nginx/html
+
+# Copy nginx configuration
+COPY nginx.conf /etc/nginx/conf.d/default.conf
+
+EXPOSE 80
+
+CMD ["nginx", "-g", "daemon off;"]