v1.5.9

🐛 Bug Fix

• Fix opening color mismatch when same opening exists as both white/black in pool (#101)
  • Frontend: send composite key (name::color) instead of stripping color
  • Backend: parse composite key and match by name + color (12+ locations)

✅ Test

• Add E2E test (Test 30) reproducing the exact bug scenario with Najdorf sub-variations