…rborhub#5023)

Add progress tracking component for tutorial series with persistent localStorage storage:
- ProgressTracker.jsx: React component tracking completion status per lesson
  - Circular progress indicator with percentage display
  - Statistics panel (completed, remaining, estimated time)
  - Expandable lesson list with toggle checkboxes
  - Quick actions: Complete All, Reset progress
  - Persistent storage to localStorage using seriesId key
  - Callback support for progress updates

- ProgressTracker.module.css: Professional styling with animations
  - Responsive grid layout for desktop/mobile
  - Circular progress visualization with SVG
  - Progress bar with gradient fill
  - Lesson item cards with hover states
  - Celebration message on completion
  - Encouragement messages based on progress level

- ProgressTrackerExample.mdx: Complete documentation
  - Usage examples with basic and advanced props
  - Props and lesson object structure reference
  - Customization and accessibility guide
  - Time estimation algorithm explanation
  - Storage management and browser compatibility

Features:
✓ Visual circular progress indicator (0-100%)
✓ Statistics: completed lessons, remaining, estimated time
✓ Per-lesson completion toggle with persistent storage
✓ Complete all / reset progress actions
✓ Collapsible lesson list for clean UI
✓ Automatic time estimation (0.5h per uncompleted lesson)
✓ Celebration message on 100% completion
✓ Progress-based encouragement messages
✓ Mobile responsive design
✓ Keyboard accessible controls
✓ localStorage persistence per seriesId
✓ Progress callback for backend sync