Feature: Implement Skeleton Loading Screens for Show Table UI Components

[fuongz]

Summary

Add skeleton loaders to improve perceived performance during data fetches when select a table.

Motivation

• Users see blank screens during async loads, leading to poor UX.
• Skeletons/Spinner loading component show

Proposed Changes

• Show table action
• States: loading → skeleton → success/error.

Implementation Plan

1. Create reusable <Skeleton /> component.
2. Integrate with existing fetch hooks (e.g., isLoading prop)