Hide Empty Blocks for Faster Group Editing

We've added a toggle to streamline working with large room blocks.
What's new:
✔️ New checkbox to show/hide unassigned rooms in Groups
⚡️ Significant performance boost for blocks with 50+ rooms
🔒 All current selections preserved when toggling views
Why it matters:
• Faster loading when editing complex groups
• Cleaner workspace when managing partial blocks
• Same great functionality - just more efficient
Try it:
Open any Group with room blocks
Click Edit
Look for "Show empty blocks" checkbox
Toggle to match your workflow