Implements comprehensive multi-selection support for bulk operations on
actors, relations, and groups.
Features:
- New MultiSelectProperties panel for 2+ selected elements
- Bulk operations: group, ungroup, delete, minimize/maximize
- Add actors to existing groups (expands group bounds)
- Reverse relation directions
- Change directionality for multiple relations
- Immediate UI feedback with local state for directionality
- Standardized panel layout with scrollable content and footer
Fixes:
- Group positioning: actors stay at absolute positions when added/removed
- Minimize/maximize: properly stores/restores dimensions and visibility
- Position conversion between absolute and relative coordinates
- Type-safe width/height handling for group dimensions
UI Consistency:
- All property panels use fragment wrapper pattern
- Scrollable content area with px-3 py-3 padding
- Fixed footer section with action buttons
- Consistent button styles across panels
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
