test: added test cases for dialog and drawer

Description:

This PR adds comprehensive unit test cases for UI components:

• dialog.tsx (Radix UI-based modal)
• drawer.tsx (Vaul-based bottom sheet)

The tests ensure full coverage of rendering, user interactions, controlled/uncontrolled behavior, accessibility, edge cases, and integration with utility functions.

Dialog Tests (dialog.test.tsx)

• Total: 43 tests

• Covers:

  • Rendering (dialog structure, header, footer, overlay, portal)
  • User interactions (open, close, Escape key, overlay click)
  • Controlled & uncontrolled states (open, defaultOpen, onOpenChange)
  • Conditional UI rendering
  • Callback validations
  • Accessibility (role="dialog", focus, labels)
  • Edge cases (rapid toggling, null children, empty values)
  • Component-specific behavior (asChild support)
  • Integration with cn utility
  • Complete dialog lifecycle flow

Drawer Tests (drawer.test.tsx)

• Total: 51 tests

• Covers:

  • Rendering (drawer structure, handle, overlay, portal)
  • User interactions (open, close, Escape key, overlay click)
  • Controlled & uncontrolled states
  • Conditional UI rendering
  • Callback validations
  • Accessibility compliance
  • Edge cases
  • Component-specific behavior (asChild)
  • Integration testing (cn utility, shouldScaleBackground)
  • Complete drawer lifecycle flow

Key Highlights

• Tests use Jest + React Testing Library
• Only external UI primitives (Radix/Vaul) are mocked
• Actual component implementations are tested for accurate coverage
• All sub-components are validated (Trigger, Content, Header, Footer, Title, Description, Close, Overlay, Portal)

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Type of Change:

• Bug Fix
• Feature Development
• Documentation

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Testing:

• Tested on desktop
• Tested on mobile
• Tested in different browsers

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Screenshots (if applicable):

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Checklist:

• Code follows project style guidelines
• Self-review completed
• No console errors
• TypeScript types are correct

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closes #272 (closed)