improve: optimize admin dashboard statistics and user experience

[qowlgur121]

Summary

Optimize dashboard statistics display and enhance user experience by removing inaccurate metrics and improving refresh rates.

Changes Made

• Statistics Optimization: Remove inaccurate Total Chunks and Indexed cards (no backend API available)
• Layout Improvement: Streamline to 4 accurate statistics cards with balanced grid layout
• Performance Enhancement: Improve refresh rate from 30s to 5s for near real-time updates
• Code Cleanup: Remove unused imports and optimize component structure

Key Implementation Notes

• Pattern: Dashboard now displays only accurate document-level statistics
• Testing: Verified 5-second polling works correctly with real API data
• API Integration: Uses existing getDocuments endpoint for reliable statistics
• Performance: Optimized grid layout (lg:grid-cols-4) for better visual balance

Statistics Cards Overview

• Total Documents - Count of all uploaded documents
• Completed - Successfully processed documents (with success rate)
• Processing - Documents currently in pipeline (PENDING → INDEXING)
• Errors - Documents that failed processing (need attention)

Technical Details

• Refresh Rate: 30s → 5s for better status monitoring
• Grid Layout: 3-column → 4-column for optimal card distribution
• Data Source: Real-time statistics from /api/v1/sources endpoint
• Removed Components: Total Chunks, Indexed cards (inaccurate without dedicated API)

Testing Completed

• Dashboard loading performance verified
• 5-second auto-refresh functionality confirmed
• All 4 statistics cards show accurate real-time data
• API error handling works correctly

[Copilot]

Pull Request Overview

This PR optimizes the admin dashboard by removing inaccurate statistics and improving user experience through faster refresh rates and better layout.

• Removes Total Chunks and Indexed statistics cards that lack proper backend API support
• Improves refresh rate from 30 seconds to 5 seconds for near real-time updates
• Updates grid layout from 3 columns to 4 columns for better visual balance

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[Copilot]

A 5-second refresh interval may cause excessive API calls and unnecessary load on the backend. Consider if 5 seconds is truly necessary for this use case, or if a slightly longer interval (e.g., 10-15 seconds) would provide sufficient real-time updates while reducing server load.

Suggested change

	refetchInterval: 5000, // Refetch every 5 seconds
	refetchInterval: 10000, // Refetch every 10 seconds

[Copilot]

The 'Search' import from lucide-react appears to be unused after removing the indexed chunks card. Consider removing this unused import to keep the code clean.

Suggested change

	Search
	Server