FEAT: Add 5-hour billing block tracking and enhanced project view

[MiwiDots]

Summary

• Implement real-time billing block tracking aligned with Claude's 5-hour cycles
• Add granular token tracking with breakdown by type (input/output/cache-creation/cache-read)
• Create enhanced project view with advanced filtering and live monitoring

Key Features

1. Billing Block Tracking

• Real-time tracking of Claude's 5-hour billing windows
• Visual progress bars with color-coded burn rate indicators
• Accurate cost projections based on current usage patterns
• Proper hour flooring for first entry in each block (matching ccusage behavior)

2. Enhanced Project View

• Replaced simple "Top 5 Projects" list with comprehensive ProjectGridView
• Added search functionality for finding projects by name or path
• Filter options: All, Active Only, Recent Activity, High Cost (>10%)
• Sort options: Cost, Name, Last Used, Efficiency, Burn Rate
• Live monitoring mode with auto-refresh capabilities
• Activity indicators showing real-time project status

3. Token Breakdown

• Granular tracking of all token types:
  • Input tokens
  • Output tokens
  • Cache creation tokens
  • Cache read tokens
• Efficiency metrics (cost per 1000 tokens)
• Burn rate calculations using only non-cache tokens

4. Internationalization

• Full translations for all 6 supported languages
• Currency conversion integrated throughout billing components
• Localized number and date formatting

Technical Details

• Created new TypeScript types for billing blocks in src/shared/types/billing.ts
• Implemented BillingBlockService for managing billing data
• Added utility functions for billing calculations in src/shared/utils/billingBlocks.ts
• Enhanced IPC communication for billing block data
• React components use memoization for optimal performance

Testing

• Manually tested billing block calculations against ccusage project
• Verified hour flooring behavior matches expected Claude billing windows
• Tested all filtering and sorting options in ProjectGridView
• Confirmed translations work correctly in all languages
• Verified currency conversion throughout components

Screenshots

Components integrate seamlessly into existing UsageDashboard with matching theme support.