Add comprehensive GenAI testing scenarios

[ajeetraina]

This PR adds comprehensive integration tests for GenAI applications using Testcontainers.

New Test Scenarios Added

1. Prompt Handling & Response Validation

   • Tests different types of prompts
   • Validates response structure and content
   • Ensures responses match expected formats

2. Performance Testing

   • Measures response latencies for different complexity prompts
   • Tests concurrent request handling
   • Reports detailed timing metrics

3. Error Handling

   • Tests malformed JSON requests
   • Tests invalid endpoints
   • Tests missing required fields

4. Context Window Testing

   • Tests model behavior with varying context sizes
   • Monitors token usage

Implementation Details

• Added helpers and utility functions in helpers.go
• Created separate test files for each testing category
• Included comprehensive documentation in README.md
• Tests are configurable to run against local or containerized environments
• Added short mode support to skip resource-intensive tests

How to Use

Run all tests:

cd tests/
go test -v ./integration

Run specific test:

go test -v ./integration -run TestPromptHandling

These tests demonstrate how to comprehensively test GenAI applications in isolated, reproducible environments using Testcontainers.