Improvements on usage page

We made several major improvements to the usage page:

• You can now see how long each request takes, and there's a dedicated page to view all your requests where the request table is expanded, making it easier to explore and analyze your data.
• We've improved the empty state for all charts to make things clearer when there's no data.
• The loading experience is now smoother.
• Fixed an issue where the total request count wasn't displaying correctly.