Update README and documentation; refactor frontend components for improved structure and resilience

frontend/RESILIENCE.md

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+# Frontend Resilience Features
+
+The LabFusion frontend is designed to work gracefully even when backend services are unavailable.
+
+## Features
+
+### 1. Service Status Monitoring
+- **Real-time Health Checks**: Monitors all backend services every 30 seconds
+- **Service Status Banner**: Shows current service availability status
+- **Automatic Retry**: Attempts to reconnect when services come back online
+
+### 2. Graceful Degradation
+- **Fallback Data**: Uses sample data when services are unavailable
+- **Error Handling**: Displays helpful error messages instead of crashes
+- **Loading States**: Shows loading indicators during data fetching
+
+### 3. Offline Mode
+- **Offline Banner**: Clear indication when all services are down
+- **Instructions**: Step-by-step guide to start backend services
+- **Retry Button**: Easy way to attempt reconnection
+
+### 4. Error Recovery
+- **Timeout Handling**: 5-second timeout for all API calls
+- **Connection Error Detection**: Distinguishes between different error types
+- **User-Friendly Messages**: Clear explanations of what's happening
+
+## Service Status States
+
+### Online
+- All services are running normally
+- No status banner shown
+- Full functionality available
+
+### Partial
+- Some services are unavailable
+- Warning banner with service details
+- Limited functionality with fallback data
+
+### Offline
+- All backend services are down
+- Offline mode banner with instructions
+- Frontend runs with sample data only
+
+## API Configuration
+
+The frontend automatically detects service availability:
+
+```javascript
+// Service URLs (configurable via environment variables)
+API_GATEWAY_URL=http://localhost:8080
+SERVICE_ADAPTERS_URL=http://localhost:8000
+API_DOCS_URL=http://localhost:8083
+```
+
+## Development
+
+### Running Frontend Only
+```bash
+cd frontend
+npm install
+npm start
+```
+
+The frontend will start and show offline mode until backend services are started.
+
+### Testing Resilience
+1. Start frontend: `npm start`
+2. Observe offline mode banner
+3. Start backend: `docker-compose up -d`
+4. Watch automatic reconnection
+5. Stop backend services to test fallback
+
+## Error Messages
+
+- **Connection Timeout**: "Request timeout - service may be unavailable"
+- **Service Error**: "Service error: [HTTP status]"
+- **Service Unavailable**: "Service unavailable - check if backend is running"
+- **Unknown Error**: "Unknown error occurred"
+
+## Benefits
+
+- **Developer Experience**: Frontend can be developed independently
+- **User Experience**: Clear feedback about service status
+- **Debugging**: Easy to identify which services are having issues
+- **Reliability**: App doesn't crash when services are down