docs: update changelog for v0.0.21 [skip ci]

Bump version: 0.0.20 → 0.0.21

feat: Add comprehensive documentation and improve README structure

docs: update changelog for v0.0.20 [skip ci]

Bump version: 0.0.19 → 0.0.20

Add comprehensive documentation for LLMEvaluationFramework (v0.1.0)

docs: update changelog for v0.0.19 [skip ci]

Bump version: 0.0.18 → 0.0.19

Refactor CLI tests: Enhance main module execution test and remove redundant test file

Add comprehensive tests for persistence layer including JSONStore, DBStore, and PersistenceManager

Implement JSONStore for evaluation results persistence, enhance TestDatasetGenerator with type hints, add error handling utilities, and establish centralized logging. Update setup.py for dependencies and entry points, and create requirements.txt for core and development dependencies.

Update index.md

Update index.md

Update index.md

docs: update changelog for v0.0.18 [skip ci]