Add loader for every page

Since the app is deployed in a free service, it is expected that the app will run pretty slow. Its pleasant to see the pages to have loader after loading the actual data.

Also considering implementation of skeleton loaders

No files, tests, or explicit entry points are listed in the issue body. Start from the app’s main render/navigation layer to see how each page transition and async fetch is orchestrated, then add or reuse a shared loading UI so every page shows a visible loader during waits. Verify behavior by running the app and manually checking page navigation and data-loading paths across the app to confirm consistent loader/skeleton behavior.

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