- **Tests**: Added new `statistics-storage.test.ts` to validate statistics storage functionality across scenarios including saving, retrieving, time-based partitioning, and backward compatibility. Ensured tests dynamically handle missing environment variables by skipping S3-related tests when credentials are unavailable.
- **Docs**: Enhanced `statistics.md` with detailed explanations of scalability improvements, including adaptive flush timing, batched updates, and time-based partitioning. Improved readability and structure.
- **Storage**: Updated all storage adapters to integrate time-based partitioning and maintain backward compatibility with legacy statistics storage formats.
- **Dependencies**: Added `dotenv` to support environmental variable management for storage adapter tests.
**Purpose**: Strengthen system reliability by adding comprehensive test coverage for statistics storage, improve scalability documentation, and ensure consistency across storage adapters with robust implementations.
