Add request validation, DTOs, new IoT analysis endpoints, and real-time WebSocket streaming

[abhinavsharma72]

Validation added (Zod)
• Installed zod.
• Created BackendCode/middleware/validateRequest.js for reusable request validation.
• Added BackendCode/validation/schemas.js with endpointspecific schemas.
• Wired validation into BackendCode/routes/mock.js so inputs are checked at the boundary.

Controllers updated
• mockController.js and pythonController.js now use req.validatedBody when present, reducing defensive code and runtime errors.

DTOs for consistent responses
• Added BackendCode/dtos/index.js with mapEntryDto and
mapEntriesDto.
• Applied to GET /api/streams and POST /api/filterstreams to normalize response shape.

Documentation improved
• Expanded README.md:
• Full project structure and file purposes
• Validation and DTO sections with sample 400 error payload
• Copy-pasteable curl examples for all endpoints

IoT Project Features
New API Endpoints
POST /api/correlations: correlation analysis with multiple algorithms
POST /api/anomalies: Z-score anomaly detection across streams
POST /api/export: export data (JSON/CSV) with date range & filtering
GET /api/algorithms, GET /api/statistics: ML algorithms + dataset metadata

WebSocket Integration:-

Real-time data streaming (ws://localhost:8080)

Stream subscriptions + on-demand correlation/anomaly detection
ML Algorithm Integration
Correlation coefficient calculation
Z-score anomaly detection (configurable thresholds)
Stream/date filtering and statistical analysis

Complete Data Flow
Frontend → API → Service Layer → Repository → Mock Data
Real-time WebSocket communication
JSON/CSV export functionality
Robust error handling and validation