feat: Add flexible port configuration for development

- Change default ports to 7510 (backend) and 7511 (frontend) to avoid conflicts
- Add PORT environment variable support for both services
- Create docker-compose.dev.yml for development without SSL/nginx
- Add development script (scripts/dev.sh) for easy local development
- Create comprehensive port configuration documentation
- Update docker-compose.yml to support dynamic port configuration
- Add frontend .env.example with development settings

This allows running the application on custom ports internally without SSL,
making it easier to integrate with existing infrastructure.

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

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

docker/Dockerfile.frontend.dev

@@ -0,0 +1,22 @@
+# Development Dockerfile for frontend
+FROM node:20-alpine
+
+WORKDIR /app
+
+# Copy package files
+COPY package*.json ./
+
+# Configure npm to use legacy peer deps
+RUN npm config set legacy-peer-deps true
+
+# Install dependencies
+RUN npm install
+
+# Copy application files
+COPY . .
+
+# Expose the development server port
+EXPOSE 7511
+
+# Start the development server
+CMD ["npm", "start"]