Verify that grid preset correctly handles uneven window counts:
- 2 windows → 1×2 grid
- 3 windows → 1×3 single row
- 4 windows → 2×2 perfect grid
- 5 windows → 2×3 grid (last row expands to fill)
- 7 windows → 2×4 grid (last row expands)
- 9 windows → 3×3 perfect grid
- 11 windows → 3×4 grid (last row expands)
Key behaviors verified:
- No empty space (last row windows expand to 100% width)
- All windows preserved in layout
- Window order maintained (depth-first traversal)
- Works with any N ≥ 2 windows
Also tests:
- Side-by-side with 2-4 windows (and error for 5+)
- Main + Sidebar with various window counts
- Error handling for too few/many windows
All 22 tests pass ✓
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
