feat(frontend): add interactive UI for clarification questions

[RANDAAAALL]

Description

• Build ClarificationCard to dynamically render single_choice, multiple_choice, text, and date inputs
• Add progress bar to visualize clarification completion status
• Extract ChatInterface, MessageList, and ChatInput into separate components to align with project architecture
• Extract ItinerarySummaryCard for clean final state rendering

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Code refactoring
• Performance improvement
• Other (please describe):

Testing

• Build passes (npm run build for frontend, pytest for backend)
• Type check passes (npm run typecheck for frontend)
• Tested locally
• All existing tests pass

Screenshots / Visual Changes

After

This is just temporary since the UI design is not finalized yet.

Related Issues

• Related to [Frontend]: Build clarification question flow in ChatPage #26

Checklist

• Code follows project conventions (see ARCHITECTURE.md)
• No any types used unnecessarily (TypeScript)
• Proper error handling implemented
• Loading states added (if applicable)
• Responsive design tested (if UI changes)
• Self-review completed
• Comments added for complex logic
• Documentation updated (if needed)

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Review Notes:

Reviewer: Please indicate whether to squash commits or preserve history when merging.