Complete Backend Testing Suite, Coverage Reporting, and GitHub Actions CI Pipeline

[YogeshwaranOfficial]

Overview

This PR introduces a comprehensive backend quality assurance framework for the Library Management System, including unit testing, integration testing, code coverage reporting, and automated CI validation.

What Was Added

Unit Testing

• Added comprehensive service-layer unit tests.

• Implemented isolated mocking strategies for repositories, database models, and external SDK dependencies.

• Added test coverage for:

  • Members Module
  • Membership Plans Module
  • AI Scanner Module

Integration Testing

• Expanded end-to-end API integration coverage across backend modules.
• Validated request lifecycle behavior including controllers, services, repositories, middleware, and database interactions.

AI Scanner Testing

• Added isolated test coverage for:

  • Azure Vision OCR processing
  • Azure Translation pipeline
  • Gemini AI reasoning layer
  • OCR fallback scenarios
  • Translation failure recovery
  • LLM failure recovery
  • Empty OCR response handling

CI/CD Pipeline

• Added GitHub Actions workflow for automated backend validation.

• Configured:

  • Dependency installation
  • TypeScript build verification
  • Unit test execution
  • Integration test execution
  • Coverage report generation

• Added safe mock environment variables for CI environments to satisfy runtime validation requirements.

Test Statistics

Category	Count
Unit Tests	133
Integration Tests	102
Total Tests	235

Validation Results

• TypeScript Build: ✅ Passing
• Unit Tests: ✅ Passing
• Integration Tests: ✅ Passing
• Coverage Generation: ✅ Passing
• GitHub Actions CI: ✅ Ready

Impact

This establishes a production-grade testing foundation that helps prevent regressions, improves maintainability, and ensures all future backend changes are automatically validated before merge.