Fix Edge Weight Display Overlap

# Fix Edge Weight Display Overlap

**Priority:** Medium

## Description
Edge weight labels overlap when multiple edges are positioned close to each other, making weights difficult to read.

## Steps to Reproduce
1. Create 3-4 nodes close to each other
2. Add edges between all nodes with weights
3. Observe weight labels overlapping

## Current Behavior
- Weight labels render at fixed positions
- Labels overlap with nearby edges
- No collision detection
- Text becomes unreadable

## Expected Behavior
- Weight labels should not overlap
- Labels should be clearly readable
- Smart positioning around edges
- Consistent spacing between labels

## Proposed Solutions
- [ ] Implement smart label positioning algorithm
- [ ] Add collision detection for labels
- [ ] Create minimum spacing rules
- [ ] Add label background for better visibility
- [ ] Implement label scaling based on zoom level

## Technical Notes
- Use spatial hash grid for collision detection
- Consider force-directed label placement
- Implement label priority system
- Add option for hover-only labels

## Acceptance Criteria
- No overlapping labels in any graph configuration
- All weights should be clearly readable
- Smooth label repositioning during graph changes
- Efficient performance with many edges