TimeTable Manager Panel

🎉 Major New Feature: TimeTable Manager Panel

Complete visual management interface for school timetables, inspired by Switch Manager.

✨ Highlights

• Visual Week Grid - See your entire week at a glance (6am-6pm)
• Drag & Drop - Move lessons between days intuitively
• Resize Blocks - Adjust lesson duration with grab handles
• Undo/Redo - 20-action history with Ctrl+Z / Ctrl+Shift+Z
• Schedule Templates - Quick start with Elementary, High School, or University presets
• Import/Export - Backup and restore schedules as JSON
• Rich Editor - Color picker (12 presets) and icon picker (14 icons)
• Power User Features - Keyboard shortcuts, header action bar

🚀 Quick Start

1. Update via HACS
2. Restart Home Assistant
3. Open "⏰ TimeTable Manager" from sidebar
4. Explore the new visual interface!

🔧 Technical Details

• 2,440 lines of new frontend code
• WebSocket API integration
• Mushroom-inspired design
• Full browser support (Chrome, Firefox, Safari)

⚡ Upgrade Notes

Zero breaking changes - Fully backward compatible with v3.x

All existing schedules are preserved. Config flow still works alongside the new panel.

📚 Documentation

See complete documentation in:

• PANEL_PHASE3_COMPLETE.md - Complete feature guide
• CHANGELOG.md - Version history