Unleash 4.8: metrics and code quality

Unleash 4.8 introduces a significant update with enhanced metrics visualization for feature flags, providing users with more detailed insights into user interactions. The new release features revamped metrics tabs that now include line graphs to show feature exposure and request data over selectable time frames, such as the last 48 hours, 24 hours, or one hour, while maintaining the original pie chart visualization for quick overviews. Users can further refine their data view using environment and application controls, and raw numbers are also displayed for a comprehensive traffic overview. In addition to visual improvements, Unleash 4.8 emphasizes code quality by reducing the admin UI codebase by nearly 8,000 lines, as part of an ongoing effort to streamline the front-end architecture and remove unnecessary dependencies. This update aims to make it easier for users to understand and manage feature flag performance while ensuring the platform's underlying code remains efficient and maintainable.