[FEATURE] Add Avatar and Pagination demo entries to `components.tsx`

[durvaakadam]

Problem / Motivation

The goal is to extend component demo coverage by adding Avatar and Pagination components to components.tsx.
This enhancement ensures both components are properly imported, previewed, and type-safe within the UI component showcase.

Proposed Solution

• Import Avatar and Pagination from @/components/ui.
• Add demo entries for both components to the componentsData list.
• Include code snippets, prop data, and preview examples for each.
• Verify no TypeScript or compile errors occur after modification.

Alternatives considered

No alternative approaches were required — this is a direct enhancement to improve component coverage.

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Acceptance Criteria

• Avatar and Pagination are successfully imported into components.tsx.
• Each component includes demo preview, code snippet, and props data.
• No TypeScript or compile errors are introduced.
• Local verification passes (npx tsc --noEmit or equivalent).

[github-actions]

Welcome, @durvaakadam! Thanks for raising the issue.
Soon the maintainers/owner will review it and provide you with feedback/suggestions.
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• DevUI